Download Dow - Building Solutions

Uniclass
EPIC
L68151:P7111
F841:X722
CI/SfB
(27)
May 2006
Dow - Building Solutions
Insulating buildings with STYROFOAM
Rn7
(M2)
Contents
Introduction
Insulating Floors
About STYROFOAM
03
Basic principles
35
Developing your STYROFOAM Solution
03
Insulating groundbearing floors: design
38
Authority
03
Insulating groundbearing floors: installation
44
Meeting environmental standards
03
Insulating suspended floors: design
45
Insulating suspended floors: installation
48
Renovating floors
49
Product Data
Technical description
04
Performance
04
Insulating Structures Below Ground
Products
05
Insulating structures below ground: design
50
Handling and Storage
06
Insulating structures below ground: installation
51
Data Table
07
Insulating Walls
52
Part L 2006 Guidance
10
Insulating Single Ply Roofs
54
Insulating Pitched Roofs
56
Insulating Agricultural Buildings
60
References
62
Notes
64
Stockists
66
Insulating Inverted Flat Roofs
Insulating Inverted roofs: basic principles
14
Insulating ballasted inverted roofs:
design considerations (ROOFMATE MinK System)
18
Insulating ballasted inverted roofs:
installation methods
23
Insulating lightweight inverted roofs:
design considerations
24
Insulating lightweight inverted roofs:
installation methods
27
Insulating green roofs: design considerations
28
Insulating green roofs: installation methods
30
Insulating roofs for renovation projects:
design considerations
31
ROOFMATE LG-X Project assessment sheet
34
Note
Information contained in this brochure may be subject to change. When specifying STYROFOAM it is important to follow the most recent advice and
recommendations. Contact Dow or visit our web site at www.styrofoameurope.com
2
Introduction
In the demanding conditions of today’s building and
Developing your STYROFOAM Solution
engineering projects STYROFOAM™ blue extruded
Each construction project has its own unique combination
polystyrene boards can deliver the thermal performance
of insulation requirements. Developing an accurate
and strength you require - for the lifetime of the structure.
insulation project specification can be a time-consuming
As a world-class producer of thermal insulation products,
process. However, the designer now has available a range
Dow can provide all the help, advice and information you
of fast-track templates in the form of STYROFOAM Solutions.
need to achieve the solutions you’re looking for.
You will find each STYROFOAM Solution detailed in a
Dow has developed STYROFOAM Solutions, for using
dedicated section of this manual.
STYROFOAM to maximum effect in a wide selection of
The STYROFOAM product range itself is described in the
typical application areas.
Product Data section. Further information is available on
the STYROFOAM Solutions web site at
About STYROFOAM
www.styrofoameurope.com
STYROFOAM has been manufactured by Dow for more
than 60 years. The process of extruding foamed polystyrene
Authority
results in a material with uniformly small, closed cells, a
STYROFOAM is manufactured under a BS EN ISO 9001:2001
smooth ‘skin’ and an unrivalled set of properties which
Quality Assurance System (BSI Certificate Q05968).
make it the choice of specifiers in a wide range of
demanding insulation applications:
›››
low thermal conductivity - minimising the board
STYROFOAM products comply with BS EN 13164: 2001
Thermal insulation products for buildings - factory made
products of extruded polystyrene (XPS) - specification.
thickness needed to achieve a specific U-value, thus
allowing the designer greater flexibility.
›››
high compressive strength - in load-bearing
applications, the closed cell structure gives the foam
great rigidity and makes it highly resistant to
compression.
›››
STYROFOAM products have been evaluated by the British
Board of Agrément and certified as suitable for use in:
›››
›››
›››
Cavity walls (Certificate 88/2105).
Pitched roofs - warm roof concept
(Certificate 87/1836).
low water absorption - STYROFOAM has natural
resistance to rain, snow, frost and water vapour which
Floors (Certificate 92/2782)
›››
Inverted roofs (Certificate 97/3431).
makes it an exceptionally stable material, which retains
its initial insulation performance and physical integrity
in exposed conditions over the very long term. It was
this unusual property that made possible the inverted
warm roof concept, pioneered by Dow.
›››
›››
Meeting environmental standards
Concern about ozone depletion in the stratosphere has led
to international agreements to phase out the use of ozonedepleting chemicals.
workability - STYROFOAM is easily worked with normal
hand tools.
All STYROFOAM products are hydrochlorofluorocarbon
hygiene - STYROFOAM boards have low susceptibility
(HCFC) free and comply with the requirements of EC
to rot, mould or fungal growth is therefore minimised.
Regulation No 2037/2000 (1 Oct 2000) on substances
They are clean, odourless and free from irritating dust.
which deplete the ozone layer. STYROFOAM `X’ products
are foamed with a hydrofluorocarbon (HFC) and `A’
STYROFOAM is available in a number of different grades
products with carbon dioxide.
designed to meet the performance requirements of
specific applications.
®™* Trademark of The Dow Chemical Company ("DOW") or an affiliated company of Dow
STYROFOAM Solutions
3
Product data
Technical description
Surface characteristics
Dow STYROFOAM boards are blue. All boards have a
smooth homogeneous skin on both sides with the
exception of ROOFMATE™ LG-X and PERIMATE™ DI-A.
Performance
Structural
STYROFOAM boards are available in a range of compressive
strengths to suit different loadbearing requirements.
Fire
Information on aspects of fire performance of extruded
polystyrene in building applications is given in
BS 6203: 1991, 'Fire characteristics and fire performance of
expanded polystyrene materials used in building
applications'.
Water/moisture
STYROFOAM is highly resistant to water absorption.
STYROFOAM boards are very resistant to the passage of
water vapour and are unaffected by repeated freeze/thaw
cycles.
Biological
STYROFOAM has low susceptibility to rot; mould or fungal
growth is therefore minimised.
Chemical
STYROFOAM boards are resistant to most commonly
occurring construction materials such as lime, cement,
plaster, anhydrous gypsum, solvent-free bituminous
compounds, water-based wood preservatives, as well as
alcohols, acids and alkalis. Certain organic materials such as
solvent-based wood preservatives, coal tar and derivatives
(creosote), paint thinners and common solvents
STYROFOAM products contain a flame retardant additive to
(e.g. acetone, ethyl acetate, petrol, toluene and white spirit)
inhibit accidental ignition from a small fire source.
will attack STYROFOAM, resulting in softening, shrinkage
STYROFOAM is, however, combustible and if exposed to an
and possible dissolution, with a consequent loss of
intensive fire may burn rapidly.
performance.
During Shipment, storage, installation and use STYROFOAM
The use of solvent-free adhesives is recommended.
products should not be exposed to flames or other ignition
Advice on compatibility with polystyrene foam should be
sources.
sought from the adhesive manufacturers.
Fire classification is based on small-scale tests, which may
not reflect the reaction of the product in its end use state
under actual fire conditions.
STYROFOAM products should, when installed, be
adequately protected from direct exposure to fire.
STYROFOAM products achieve Euroclass E (reaction to fire).
Temperature
Polystyrene products will melt when brought into direct
contact with high temperature heat sources: for Dow
STYROFOAM boards the recommended maximum
continuous operation temperature is 75°C.
®™* Trademark of The Dow Chemical Company ("DOW") or an affiliated company of Dow
4
Product data
Sunlight
Products
Protect STYROFOAM from prolonged exposure to intense
FLOORMATE
sunlight to prevent degradation of the surface of the
FLOORMATE™ is the STYROFOAM Solution for insulating
board.
floors. FLOORMATE insulation is available in a range of
compressive strengths to match the loading requirements
Durability
of individual projects.
Properly installed, STYROFOAM boards have a service life
comparable with that of the building or structure.
FLOORMATE insulation can be installed under or over the
slab in groundbearing concrete floors and is suitable for
Environmental
use on suspended beam and block or timber floors.
STYROFOAM is non bio-degradable and does not present
WALLMATE
an environmental hazard.
WALLMATE™ CW-X is the STYROFOAM Solution for
Disposal
insulating walls. WALLMATE CW-X insulation can be used as
STYROFOAM can be:
partial cavity fill without increasing the risk of water
›››
›››
›››
›››
recycled mechanically.
penetration.
recycled chemically.
The low water absorption of WALLMATE CW-X insulation
used as land-fill.
enables it to be used in walls without any loss of
incinerated under control to recover the energy
performance. WALLMATE CW-X boards are sized to
content.
co-ordinate with common brick and block sizes.
Properties
Standard
Specific heat
Coefficient of linear
thermal expansion
—
BS 4370: Part 3: 1988:Method 13
Working temperature range
Fire classification:
reaction to fire
—
Unit
Value
kJ/kgK
1.4
mm/mK
0.07
°C
-50 to +75
BS EN 13164 + BS EN 13501: Euroclass E
Table 01 Common properties of STYROFOAM products
®™* Trademark of The Dow Chemical Company ("DOW") or an affiliated company of Dow
STYROFOAM Solutions
5
Product data: products
ROOFMATE SL-X & LG-X
CE marking (to BS EN 13164)
ROOFMATE SL-X and ROOFMATE LG-X are the STYROFOAM
FLOORMATE 200-X
T1 – CS(10/Y)200 - CC(2/1.5/50)60 - WL(T) 0.7 - DS(TH)
Solutions for insulating inverted roofs. The boards are
unaffected by the conditions encountered on flat roofs,
including wide fluctuations in temperature or repeated
STYROFOAM SP-X
T1 – CS(10/Y)300 - CC(2/1.5/50)120- WL(T) 0.7 - DS(TH)
freeze/thaw cycles. ROOFMATE SL-X insulation is intended
for use on heavyweight decks with a ballast layer of gravel
or concrete slabs. It can also be used in the ROOFMATE
MinK system, which will reduce the rain water cooling
penalty, thereby minimising the insulation thickness
required. Its rot-resistance makes it ideal for insulating roof
FLOORMATE 500-X
T1 – CS(10/Y)500 - CC(2/1.5/50)150 - WL(T) 0.7 - DS(TH)
FLOORMATE 700-A
T1 – CS(10/Y)700 - CC(2/1.5/50)250 - WL(T)0.7
- WD(V)3 - FT2 - DS(TH) - DLT(2)5
gardens.
ROOFMATE LG-X boards have a 10mm modified concrete
WALLMATE CW-X
T1 – CS(10/Y)100 - WL(T) 0.7 -DS(TH)
topping on the upper surface, eliminating the need for
separate ballast and making it possible to gain the benefits
ROOFMATE RL-X
T1 – CS(10/Y)300 - WL(T) 0.7 - DS(TH)
of the inverted roof on lightweight decks.
ROOFMATE RL X
ROOFMATE RL-X is the STYROFOAM solution for insulating
single-ply roof decks. ROOFMATE RL-X boards provide a
lightweight, rigid substrate beneath light-coloured
single-ply polymeric membranes on flat or low slope metal
decked roofs. The large area and high dimensional stability
ROOFMATE SL-X
T1 –CS(10/Y)300 - CC(2/1.5/50)110 - WL(T) 0.7 - WD(V)3
- FT2 - DS(TH) - DLT(2)5
ROOFMATE LG-X †††
T1 – CS(10/Y)300 - CC(2/1.5/50)110 - WL(T)0.7 - WD(V)3
- FT2 DS(TH) - DLT(2)5
PERIMATE DI-A†††
of ROOFMATE RL-X boards minimise the installation time as
well as the number of fixings required.
T1 – CS(10/Y)300 - WL(T)0.7 - WD(V)3 - FT1 - DS(TH)
ROOFMATE RL-X can also be used to insulate warm pitched
roofs at rafter line. ROOFMATE RL-X boards are for
installation above the rafters with ROOFMATE RL-X boards
cut to size to fit between the rafters The insulation is
supplied in large boards for rapid coverage.
PERIMATE DI-A
PERIMATE DI-A is the STYROFOAM solution for insulating
structure below ground. PERIMATE DI-A boards have
vertical channels cut into one face, to drain water away,
and a filter fabric bonded to the face to prevent soil
particles blocking the channels.
6
†††
Insulation only
FLOORS
WALLS
ROOFS
◆
Domestic
Medium load bearing
High load bearing
V high load bearing
Partial fill cavity
Below ground/basement
◆
◆
ROOFMATE LG-X
ROOFMATE SL-X
ROOFMATE RL-X
WALLMATE CW-X
FLOORMATE 700-A
FLOORMATE 500-X
STYROFOAM SP-X
PERIMATE DI-A
FLOORMATE 200-X
Product data: data tables
◆
◆
◆
Pitched - insulation at
rafter line
Flat: inverted
-ballasted
-lightweight
-terraced
Flat: conventional warm
◆
◆
◆
◆
AGRICULTURAL BUILDINGS
◆
◆
◆
◆
ROOFMATE RL-X
ROOFMATE SL-X
ROOFMATE LG-X
WALLMATE CW-X
1.70
1.70
2.05
2.05
2.05
2.05
2.05
2.4
2.40
30
1.00
35
1.20
40
1.35
50
1.70
70
FLOORMATE 700-A
1.70
0.85
1.70
FLOORMATRE 500-X
1.70
25
60
STYROFOAM SP-X
mm
FLOORMATE 200-X
Thickness
PERIMATE DI-A
Table 02 Product Selector
75
1.20
1.35
1.70
1.70
1.35
2.55
2.55
80
2.75
2.75
2.75
2.75
90
3.10
3.10
3.10
3.10
100
2.75
3.45
120
3.30
4.10
140
4.50
4.10
4.10
2.75
3.45
3.45
4.10
4.10
4.50
4.50
150
4.85
160
5.15
5.15
180
5.80
5.80
200
6.45
Table 03 Declared thermal resistance (RD) - m2K/W
STYROFOAM Solutions
7
Product data: data tables
FLOORMATE 200-X
STYROFOAM SP-X
Properties
Standard
unit
CE Code
Thermal conductivity*
≤80mm
81-120
>121
BS EN 12667
BS EN 12667
BS EN 12667
W/mK
W/mK
W/mK
λD
λD
λD
0.029
0.029
0.031
0.029
0.029
-
Compressive strength
at 10% or break (90
days)
BS EN 826
kN/m2
CS(10/Y)i
200
350
Design load
2% max. deflection
(50 years)
BS EN 1606
kN/m2
CC(2/1.5/50) σc
60
110
BS EN 12086
MNs/gm
-
825
875
MUi
165
175
Water vapour resistivity
Water vapour diffusion
resistance factor
BS EN 12086
m
Water absorption
Total immersion
Diffusion
Freeze/thaw, after
300 cycles
BS EN 12087
BS EN 12088
BS EN 12091
% vol
% vol
% vol
WL(T)i
WL(V)i
FTi
<0.5
-
<0.5
-
Dimensional stability
48hrs at 70C/90%
RH
168hrs at 40kPa/70C
BS EN 1604
BS EN 1605
%
%
DS(TH)
DLT(2)5
<2
-
<2
-
Density (aim)
BS EN 1602
kg/m3
-
38
38
Dimensions
Length
Width
Thickness
BS EN 822
BS EN 822
BS EN 823
mm
mm
mm
Ti
2500
600
25, 30, 35, 40, 50, 60,
70, 80, 90, 100, 120,
140
2500
600
50, 75
Fire classification
– reaction to fire
BS EN 13164
BS EN 13501
Euroclass
E
E
Appearance
Surface
Edge profile
skin
butt edge
skin
butt edge
Application
Floors - domestic
Floors medium load bearing
92/2782
92/2782
Certification
BBA Agrément
-
-
-
Table 04 Product data
The properties given above are typical (unless stated otherwise). Results of tests described are available from Dow.
* declared 90/90 value - BS EN 13164
** includes 10 mm for the mortar topping; thicker products available on request up to 190 mm
8
Product data: data tables
FLOORMATE
500-X
0.029
0.029
-
FLOORMATE
700-A
WALLMATE CW-X
ROOFMATE
RL-X
ROOFMATE
SL-X
ROOFMATE
LG-X
PERIMATE DI-A
0.036
-
0.029
0.029
-
0.029
0.029
-
0.029
0.029
0.031
0.029
0.029
0.031
0.035
0.036
-
700
200
300
300
300
300
110
110
110
500
250
150
825
575
825
825
825
825
165
165
115
165
165
165
165
<0.5
<3
<1
<0.5
<3
<1
<0.5
-
<0.5
-
<0.5
-
<0.5
<3
<1
<0.5
<3
<1
<2
-
<2
<5
<2
-
<2
<5
<2
<5
<2
40
45
38
38
38
38
45
1250
600
50, 80, 120
1250
600
50
1200
450
50, 60, 70,
80, 90
2500
600
50, 60, 80,120
1250
600
50, 60, 75, 80, 90
100, 120, 140, 160, 180,
200
1200
600
60, 70, 90, 110, 130**
1250
600
60, 100 120
E
E
E
E
E
E
E
skin
shiplap
skin
shiplap
skin
shiplap
skin
tongue & groove
skin
shiplap
mortar topping
tongue & groove
grooved face &
geotextile shiplap
Floors high load
bearing
Floors very high
load bearing
Cavity wall - partial fill
Pitched roofs
insulation at rafter line
Flat roofs
Agricultural
Inverted roofs
ballasted
Inverted roofs
lightweight
Basement walls
external
92/2782
-
88/2105
87/1836
97/3431
97/3431
825
<2
-
STYROFOAM Solutions
9
Part L 2006 Guidance
6 April 2006 saw the introduction of changes to Part L of
the Building Regulations in England and
Wales†.
selected method is a revised version of the
›››
›››
›››
›››
›››
›››
›››
›››
›››
›››
›››
government’s Standard Assessment Procedure
Demonstrating compliance for extensions to and
(SAP 2005), whilst for other buildings the government
refurbishment of existing buildings, especially dwellings,
has introduced the Simplified Building Energy Model
will still rely heavily on elemental U-values.
(SBEM).
There are now four new Approved Documents:
reduce the UK’s emissions of greenhouse gases,
particularly carbon dioxide. The operation of buildings
accounts for 46% of the UK’s carbon dioxide emissions;
the intention behind the regulations is to reduce
emissions for new buildings by 20 - 28% compared to
the 2002 regulations.
›››
implement parts of the European Union’s Energy
Performance of Buildings Directive, which requires the
introduction of standardised methods of assessing the
energy efficiency of buildings. For dwellings the
›››
requires simultaneous consideration of all factors affecting
energy efficiency including:
The changes are intended to:
›››
This holistic approach offers greater design flexibility but
reduce fuel poverty.
type of building and its configuration
siting and orientation
fenestration
elemental U-values
air leakage rate
thermal bridging
space heating/solar gain/space cooling
water heating
lighting efficiency
ventilation
type of fuel (for dwellings only).
L1A New dwellings
Meeting Part L 2006 Requirements
L1B Work on existing dwellings
The latest changes to Part L of the Building Regulations
L2A New buildings other than dwellings
complete the move towards a single compliance route for
L2B Work on existing buildings other than dwellings
all new buildings. The change, which began in 1995 with
the introduction of SAP ratings for new dwellings, requires
designers to adopt a 'whole building' approach and to
demonstrate that carbon dioxide emissions from the new
building will not exceed a stipulated maximum.
†
similar changes are expected to be introduced in Northern Ireland
in November 2006 and in Scotland in 2007
Improvement factor
LZC benchmark††
Overall improvement factor
without LZC benchmark
dwellings
20%
N/A
20%
non dwellings
- naturally ventilated
- mechanically ventilated
- air conditioned
15%
20%
20%
10%
10%
10%
23.5%
28.0%
28.0%
†† The LZC benchmark is intended to implement Article 5 of the EPBD by ensuring the use of LZC energy supply systems is considered before construction starts.
Table 05 Improvement factors and low or zero carbon (LZC) benchmarks
10
Part L 2006 Guidance
For dwellings (up to 450m2 floor area) the calculations use
New buildings
Approved Documents L1A & L2A
the SAP 2005 methodology implemented in an approved
These set out five criteria which must be met if a new
SAP program. For other buildings the calculations are
building is to meet the requirements of Part L. The criteria
performed by the SBEM, using software from the ODPM
apply to dwellings and to buildings other than dwellings,
augmented if necessary by other approved software. Both
although the methods of demonstrating compliance vary
methods take account of heat loss through air infiltration
between building types.
and thermal bridging.
1. Achieving the Target carbon dioxide emission rate.
2. Limits on design flexibility
Carbon dioxide emissions from the proposed building
The emissions rating assessment allows designers
must be lower than a target rate. The process for
considerable flexibility in the methods they employ to
calculating the target and design rates is:
achieve the required rating. To ensure the building’s fabric
1.
calculate the carbon dioxide emissions per square
and services are reasonably energy efficient they must
metre of floor area from a notional building of the
perform no worse than the limits set out in the Approved
same dimensions as the proposed building, which
Documents - see table 07. An air permeability limit of
would have passed the 2002 regulations by the
10m3/m2/hr @ 50Pa applies to all buildings.
Elemental method. – see table 06
2.
apply an improvement factor and a low or zero carbon
(LZC) benchmark (see table 05) to the calculated rate:
the resultant figure is the Target carbon dioxide
emission rate, the TER.
3. Limiting the effects of solar gains in summer
Lowering elemental U-values and improving airtightness
bring a risk of building interiors overheating in summer as a
result of solar gain. Both SAP and SBEM assessments will
test for overheating and indicate if there is an excessive risk.
For dwellings:
TER = (CH x fuel factor + CL) x (I - improvement factor)
CH = carbon dioxide emissions from heating and hot water
CL = carbon dioxide emissions from lighting
For non - dwellings:
TER = Cnotional x (I - improvement factor) x (I - LZC benchmark)
Dwellings
Non - dwellings
Walls
0.35
0.35
calculate the carbon dioxide emission rate for the
Floors
0.25
0.25
proposed building: the Dwelling emission rate (DER)
Roofs – Pitched
Flat
0.16
(0.25)
0.16
0.25
Windows/Doors
2.0
2.2
Cnotional = carbon dioxide emissions from a notional buiding
3.
for dwellings, or the Building emission rate (BER) for
other buildings.
4.
Table 06 Elemental U-values for 2002 notional buildings(W/m2.K)
the building meets the criterion if the DER or BER is
equal to or lower than the TER.
Area weighted average
Worst for any sub-element
Walls
0.35
0.70
Floors
0.25
0.70
Roofs
0.25
0.35
Windows
2.2
3.3
Doors
2.2
3.3a/3.0b
a
b
dwellings
non - dwellings
Table 07 Limiting U-values – New build (W/m2.K)
STYROFOAM Solutions
11
Part L 2006 Guidance
4. Quality of construction and commissioning
Thermal element
The standard of construction must ensure the actual
New➀
Replacement➁
Walls
0.30
0.35
Floors
0.22
0.25
The thermal insulation must be reasonably continuous
Roofs – Pitched (rafters)
(joist)
Flat
0.20
0.16
0.20
0.20
0.16
0.25
around the building envelope. Designers should use
Windows
1.8
2.0
approved construction details or be able to
Doors
3.0➂/6.0➃
3.0➂/6.0➃
performance of the building is consistent with the
predicted carbon dioxide emission rate. To achieve that:
›››
demonstrate equivalent levels of performance in
proposed alternative details.
›››
measured air permeabilities must be lower than the
values used in the emissions calculation and less than
10m3/m2/hr @ 50Pa. Whilst all buildings other than
dwellings must be tested, only a sample of dwellings
➀ Extensions to non-dwellings which are greater than 100m2 in floor area
and more than 25% of the floor area in the existing building come
under ADL2A
➁ If > 25% of surface area is to be renovated then whole element has to
be upgraded to this level
➂ Dwellings
➃ Non - Dwellings
Table 08 Extensions & Renovations – U-values (W/m2.K)
within a development need be tested (the size of the
sample depends upon the adoption of approved
›››
construction details and the results of the first test.)
Thermal element
building services must be properly commissioned:
in some cases that may involve air leakage testing
of ductwork.
5. Operating and maintenance instructions.
The owner of the building must be provided with sufficient
information to enable the fixed building services to be
efficiently operated and maintained.
Threshold
Improved
Cavity Wall
0.70
0.55
Other wall type
0.70
0.35
Floors
0.70➂/0.35➃
0.25
Roofs – Pitched (rafters)
(joist)
Flat
0.35
0.35➂/0.16➃
0.35
0.20-0.25
0.16
0.25
If U-value is worse than “threshold” then upgrade to “improved” if
economically viable (15 years payback or less)
➂ Dwellings
➃ Non - Dwellings
Table 09 Upgrade of retained thermal elements – U-values (W/m2.K)
Existing buildings
Approved Documents L1B & L2B
Because existing buildings account for a substantial
proportion of carbon dioxide emissions the revisions to
Part L have raised performance standards for building
fabric and services for extensions, material alterations and
changes of use – tables 08 and 09.
For buildings other than dwellings, work on extensions and
initial fit out may require improvements to be made to
existing services. Those ‘consequential improvements’ may
cost as much as 10% of the proposed work. Increases in
the capacity of heating or cooling plant will require
consequential improvements to the thermal elements:
there is no cost limit on such improvements, but they
should have a payback period not exceeding 15 years.
12
Part L 2006 Guidance
Transitional arrangements
Designers should consider a two stage approach: first,
Where work on site began before 6 April 2006 a building
design the building to require the minimum amount of
will only have to comply with the requirements of
heating, cooling and lighting for its operation; secondly
Part L 2002. Similarly, a building need only comply with
provide those services with the minimum carbon dioxide
Part L 2002 if the local authority has granted full plans
emissions. To do that designers may have to adopt different
approval before 6 April 2006 and work begins on site
forms of construction and it may be that some
before 1 April 2007. In most other cases the building must
constructions will be unable to give the performance
meet the requirements of Part L 2006 –
required by the regulations.
see ODPM Circular 03/2006.
Implementing the regulations
The key challenge for designers is to design buildings
which will produce 20 - 28% less carbon dioxide emissions
(some clients may, require buildings with emission levels
much lower than the bare minimum set by Building
Regulations).
Insulation will continue to play a dominant role in
achieving the carbon dioxide emissions targets in both
new and existing buildings as can be see from table 10.
Part L: 2006 ensures that the emphasis will not shift away
from the long-term benefits of insulating the building
fabric towards the short-term benefits of 'renewable' plant.
2002
All buildings
2006
Dwellings
Non - Dwellings
Natural ventilation
Mechanical ventilation
LZC
-
10%
0%
10%
0%
Overall improvement factor
20%
15%
23.5%
20%
28%
Flat roofs
0.25
0.20
0.21
0.19
0.20
0.18
Floors
0.25
0.20
0.21
0.19
0.20
0.18
Walls
0.35
0.28
0.30
0.27
0.28
0.25
Pitched roofs
0.20
0.16
0.17
0.15
0.16
0.14
Table 10 2006 U-values (W/m2.K): Impact on new build
Shows the overall improvement factor required, including any compensation for not incorporating low or zero carbon technology.
STYROFOAM Solutions
13
Insulating inverted roofs
Basic principles
The waterproof layer acts as a total vapour control layer
The performance and longevity of flat roofs depends upon
and, being on the warm side of the insulation, is
many factors, including the position of the insulation
maintained above dewpoint temperature so the risk of
within the construction.
condensation is eliminated.
If insulation is placed below the structural deck (cold roof
The inverted roof concept has other benefits.
construction) the structure remains cold and there is a
The insulation can be:
considerable risk of condensation; for that reason cold deck
›››
›››
›››
roofs are not recommended and are now seldom used.
Insulation placed above the structural deck and beneath
installed in any weather.
added to, without stripping the waterproof layer.
easily lifted and replaced/re-used if the building is
altered.
the waterproof layer (warm roof construction) reduces the
risk of condensation but, because the waterproof layer is
thermally isolated from the rest of the roof construction, it
The insulation for an inverted roof must:
is exposed to wide temperature fluctuations with
›››
›››
›››
›››
›››
›››
consequent increased risk of premature failure (Figure 01).
The inverted roof concept overcomes the problem by
placing thermal insulation above the waterproof layer,
maintaining it at an even temperature close to that of the
building interior and protecting it from the damaging
resist water absorption.
be unaffected by freeze/thaw cycling.
withstand surface traffic.
protect the waterproof layer long term.
be ballasted to prevent flotation.
be protected from UV and mechanical damage.
effects of UV radiation and from mechanical damage.
General recommendations on the design of inverted roofs
The insulation protects the waterproof covering from:
›››
›››
›››
are contained in BS 6229. Agrément certificate 97/3431
wide temperature variations - +80 to -20°C.
contains specific recommendations regarding the use of
degradation from weathering.
ROOFMATE insulation.
mechanical damage during construction, use and
maintenance.
Construction of the inverted roof
In the inverted roof system insulation is laid over the
waterproofing layer and suitably loaded to restrain it
against flotation and wind uplift and to protect it against
damage.
Inverted roof constructions can be categorised as
heavyweight or lightweight by reference to the form of
building construction involved. If the structure incorporates
protected
membrane
a concrete slab it will normally be cost-effective to design
Temperature ˚C
the slab to support the load of 80 - 120 kg/m2 imposed by
a ballasted inverted roof system (Figures 02 and 03).
0
unprotected membrane
J
F
M
A
M
J
J
A
S
O
N
Figure 01 >> Temperature fluctuations in an unprotected roof
covering compared with those in one protected by STYROFOAM
14
D
Insulating inverted roofs: basic principles
Dow also offer an alternative inverted roof solution to suit
lightweight, long span structures, capable of supporting a
minimum nominal load of 30 kg/m2.
The lightweight inverted roof features a STYROFOAM board
which, thanks to a bonded mortar topping and
interlocking edge profile, does not require an additional
ballast layer (Figure 04). This lightweight solution enables a
far wider range of buildings to gain the benefits of the
inverted roof system.
Figure 02 >> Inverted roof with aggregate ballast
The inverted roof concept is ideally suited to green roofs
where the roof is covered with a plant-bearing layer
(Figure 05). Green roofs may be used to:
›››
›››
reduce a building's environmental impact.
provide a garden area for projects where space is at a
premium.
›››
contribute to a building's appearance.
Roof loadings
Figure 03 >> Inverted roof with paving ballast
The basic roof structure may be of concrete, metal or
timber: it must be strong enough to withstand the
maximum predicted loads with a suitable factor of safety.
Inverted roofs are subject to three main loads:
›››
dead loads: the self-weight of all the materials used:
for calculation advice see BS 6399: Part 1.
›››
wind loads: the positive and negative pressures acting
on the roof should be calculated using either the
standard or directional method given in
BS 6399: Part 2.
›››
Figure 04 >> Inverted roof on light-weight deck with
self-ballasted insulation
imposed loads: see BS 6399: Part 3.
Figure 05 >> Inverted green roof
STYROFOAM Solutions
15
Insulating inverted roofs: basic principles
Thermal performance
Fire
Table 11 shows the thickness of insulation required to
achieve the expected a range of U-values now required by
Part L: 2006.
Inverted roofs ballasted with incombustible material, such
as aggregate or paving slabs, readily achieve an external
fire rating of FAA when tested to BS 476: Part 3: 1958.
In an inverted roof construction some rainwater will run off
They offer adequate resistance to the external spread of fire
beneath the insulation boards and in doing so may draw
as required by Building Regulation B4 (Regulation 19 in
heat from the deck. To compensate for this intermittent
Scotland).
heat loss it is usual to increase the thickness of insulation
by 20% (rainwater cooling penalty) or if the
For further information on the fire performance of
ROOFMATE boards the STYROFOAM Solution for roofs see
ROOFMATE MinK system is used this can be reduced to 2%
BS 6203 and Agrément Certificate 97/3431.
- see page 16.
0.20
0.18
0.16
Roof falls and drainage.
U value
0.35
0.25
Standard*
90mm
140mm 180mm 200mm 220mm
Good drainage is vital to the long-term performance of a
ROOFMATE MinK system** 80mm
120mm 160mm 180mm 200mm
flat roof. To ensure the minimum finished fall of 1:80
Roof build-up:
Ballast (aggregate or paving slabs)
Separation layer (eg. ROOFMATE MK)
ROOFMATE SL-X
recommended in BS 6229, falls should be designed to 1:40.
Inverted roof construction can be used on flat roofs
designed with falls up to 1:11. Falls must be consistent,
Separation layer
without deflections or depressions in which large
Mastic asphalt 20mm
quantities of water may pond. To perform effectively,
Sand cement screed 50mm
Concrete deck 200mm
ROOFMATE boards must not be totally submerged.
*20% rainwater cooling penalty
**2% rainwater cooling penalty
Table 11 Required ROOFMATE SL-X thickness to meet U-values (W/m2.K)
Guidance on the capacity and location of rainwater gutters
and outlets is given in BS EN 12056: Part 3. Specify
rainwater outlets which will accept run-off from both the
top of the insulation and the surface of the waterproofing.
Condensation
The inverted roof construction can greatly reduce the risk
of condensation in an existing building by keeping the roof
structure and the waterproof layer above the dewpoint
temperature.
Roof waterproofing
The inverted roof concept can be used with a wide range
of waterproofing materials, including mastic asphalt and
high performance built-up bituminous felt (bituminous
roofing felt with a core of organic fibre is not suitable).
Where the building is likely to have a high level of
humidity, as in the case of swimming pools or commercial
kitchens, condensation risk assessment should be
Where roofs do not have a fall, the waterproofing should
be to a tanking specification.
undertaken by a suitably qualified professional. A method
In renovation projects the inverted roof concept can be
for calculating the risk of interstitial condensation is given
used to upgrade thermal performance of the roof: if the
in BS EN ISO 13788.
existing waterproof layer is in sound condition it may be
Roofs with high thermal capacity - such as concrete at least
50mm thick - do not undergo rapid cooling by rainwater
run-off.
16
retained but it may be desirable to overlay it with a new
waterproof layer.
Insulating inverted roofs: basic principles
Separating layers
The recommendations for the use of separating layers in
inverted roof construction are as follows:
›››
›››
between insulation and ballast:
- to prevent fines from being washed under the
between waterproof layer and insulation:
insulation where they could damage the waterproof
- mastic asphalt: BS 8218 requires a loose-laid non-
membrane use a loose-laid filter fabric, e.g.
woven polyester fleece 130 - 140g/m2 lapped
ROOFSTAT* N or ROOFSTAT R non-woven
200 - 300mm.
geotextiles.
- bituminous felts: separating layer not normally
required.
- to maintain the depth of ballast required to counter
wind uplift at 50mm of washed 20 - 40mm nominal
- single ply polymeric membranes: a loose-laid non-
diameter aggregate irrespective of the insulation
woven polyester fleece is normally recommended
thickness, use a loose-laid non-woven geotextile
for pPVC membranes - consult the membrane
with 140g/m2 minimum density, e.g. ROOFSTAT R,
supplier.
lapped 300mm.
*Tradename of Terram Ltd.
STYROFOAM Solutions
17
Insulating ballasted inverted roofs: design considerations
General
The inverted roof system is ideally suited to the insulation
➀
of flat roofs of heavyweight construction, and offers a
➁
durable, attractive roof finish for roofs where maintenance
➂
traffic is expected (Figure 06).
➃
➄
➅
STYROFOAM Solutions
The STYROFOAM Solution for insulating ballasted
inverted roofs is ROOFMATE SL-X.
ROOFMATE SL-X is designed to give the maximum benefit
in inverted roof construction:
›››
a range of thicknesses from 50 to 200mm allows
thermal performance to be matched to project
➀
➁
➂
➃
➄
➅
ballast
separating layer (if required)
ROOFMATE SL-X
separating layer (if required)
waterproof layer
concrete slab
Figure 06 >> Ballasted inverted roof
requirements (see Table 06).
›››
shiplapped edges ensure a good interlock between
boards, which helps prevent thermal bridging.
›››
rigid boards provide a firm base for the ballast layer.
➀
For the full physical properties and performance
➁
➂
characteristics of ROOFMATE SL-X see Product Data.
➃
The ROOFMATE
MinK
➄
➅
➆
system
Allowing for rainwater cooling requires a 20% increase in
➇
insulation thickness. This can be reduced to 2% by use of
the ROOFMATE MK separating layer together with
ROOFMATE SL-X (see Agrément certificate 97/3431 - the
ROOFMATE MinK system). ROOFMATE MK is waterproof, but
at the same time water vapour permeable. It replaces the
usual separating layer laid between the insulation and
ballast (see Figure 07). Rainwater is prevented from
reaching the waterproofing layer, thereby almost
➀
➁
➂
➃
➄
➅
➆
outlet guard
ballast
ROOFMATE MK separating layer
ROOFMATE SL-X
separating layer (if required)
waterproof layer
screed to falls
➇ concrete slab
completely eliminating the rainwater cooling effect.
Figure 07 >> ROOFMATE MinK system in the inverted roof
ROOFMATE MK should be loose-laid over the insulation, at
right angles to the slope with 150mm laps running down
the slope (or if the depth of the aggregate ballast is to
kept to a maximum of 50mm then 300mm laps will be
required.) At upstands and penetrations it should be
turned up to finish above the surface of the ballast.
18
Insulating ballasted inverted roofs: design considerations
ROOFMATE MK is a spun bonded polyethylene geotextile
Aggregate should be replaced by paving slabs:-
with the following properties:
›››
›››
›››
›››
›››
water vapour permeable.
water resistant.
tear resistant.
UV stable - can be left exposed outdoors for up to four
expected.
›››
where the kerb at the roof edge is too shallow to
retain the aggregate.
›››
at perimeters, where calculations indicate aggregate
will provide insufficient resistance to wind uplift or will
months.
›››
to form walkways where regular foot traffic is
be affected by wind scour.††
fire - melts and shrinks away from a heat source
(unclassifiable as regards Building Regulations).
›››
temperature - retains flexibility and toughness down
Paving slabs
to -73ºC, melting point is 135ºC.
Table 08 lists the recommended thicknesses for paving
slabs used to ballast an inverted roof. The slabs should be
raised off the insulation on spacers to allow drainage and
Ballast
to avoid rocking. Alternatively, slabs may be set on a 20mm
Both washed aggregate and dense concrete paving slabs
bed of pea gravel or sand spread over a layer of ROOFSTAT R.
are suitable as ballast for use with ROOFMATE SL-X
The pea gravel bedding will assist drainage, support low
insulation.
strength slabs, accommodate changes of level and allow
Aggregate
This gives a good appearance at an economical cost and
the use of thinner slabs: 40mm slabs with a 20mm depth of
bedding will impose a total load of 140kg/m2.
should be 20 - 40mm nominal diameter, clean, washed and
reasonably free from fines. The depth of aggregate required
depends upon the thickness of the insulation and is shown
in Table 07.
When boards are overlaid with a suitable separating layer
(see Page 15) - such as ROOFSTAT R or ROOFMATE MK -
Thickness of
ROOFMATE SL-X
(mm)
Depth of
aggregate
(mm)
Approx weight of
aggregate
(kg/m2)†
50
50
80
60
60
96
75
75
120
90
75
120
100
80
128
120
90
144
>120 <160
100
160
>161 <200
125
200
lapped 300mm, then a 50mm depth of aggregate may be
sufficient to counter wind uplift and flotation of the
insulation. Additional ballast may, however, be needed in
those areas subject to greater wind uplift, such as
perimeters.
†
assumes density of 16kg/m2 per 10mm depth
Table 12 Recommended depth of aggregate
†
Thickness of ROOFMATE SL-X
(mm)
Thickness of paving slab†
(mm)
50, 60
not less than 40
70, 90 100, 120
not less than 50
>120
not less than 60
assumes dense concrete slabs to weigh approx. 25kg/m2 per 10mm thickness
Table 13 Recommended slab thicknesses
††
see BRE Digest 311
STYROFOAM Solutions
19
Insulating ballasted inverted roofs: design considerations
Edge details
Upstands at parapets and abutments should be protected
by ROOFMATE SL-X boards set vertically and covered with
➀
➁
an apron flashing (Figure 08).
Extending the insulation in this way affords a consistent
level of protection and helps to avoid thermal bridging.
➂
Apron flashings should be carried to at least 150mm above
➃
the surface of the ballast.
➄
Kerbs, including those at verges and rooflights, should be
➅
➆
high enough to contain the insulation and the ballast
➇
(Figure 09). ROOFMATE SL-X boards should be fitted tight
against kerbs.
➀ apron flashing
Drains and gutters
➁ ROOFMATE SL-X
Outlet gratings may be raised on spacer rings to reduce the
➂ ballast
risk of blockage: cut a hole in the ROOFMATE SL-X boards
➃ separating layer (if required)
to accommodate the outlets (Figure 10). A paving slab on
➄ ROOFMATE SL-X
spacer pads may be used above a flat grating (Figure 11).
➅ separating layer (if required)
➆ waterproof layer
Where possible, line internal gutters with ROOFMATE SL-X
➇ concrete slab
to prevent thermal bridging, and maintain the ballast layer
(Figure 12). Alternatively, the gutter may be spanned by
Figure 08 >> Ballasted inverted roof - detail at upstand
ROOFMATE SL-X boards ballasted by paving slabs on spacer
pads (Figure 13).
Where the roof drains to an edge gutter terminate
➀
aggregate ballast with a row of paving slabs on suitable
supports (figure 14) and protect the edge of the
➁
➂
➃
➄
➅
➆
➀ cover flashing or capping
➁ ballast
➂ separating layer (if required)
➃ ROOFMATE SL-X
➄ separating layer (if required)
➅ waterproof layer
➆ concrete slab
Figure 09 >> Ballasted inverted roof - detail at verge
20
ROOFMATE SL-X boards from UV light with a cover flashing.
Insulating ballasted inverted roofs: design considerations
➀
➀
➁
➂
➃
➄
➁
➂
➃
➄
➅
➆
➅
➇
➆
➈
➀ outlet guard
➁ ballast
➄ separating layer
(if required)
➂ separating layer
(if required)
➅ waterproof layer
➃ ROOFMATE SL-X
➇ concrete slab
➀ ballast
➄ waterproof layer
➁ separating layer
(if required)
➅ ROOFMATE SL-X
➂ ROOFMATE SL-X
➆ concrete slab
➃ separating layer
(if required)
➆ screed to falls
Figure 12 >> Ballasted inverted roof - insulation within internal
gutter
➈ roof outlet
Figure 10 >> Ballasted inverted roof - drain with outlet guard
➀
➁
➂
➀
➁
➂
➃
➄
➃
➄
➅
➅
➆
➀ ballast
➀ paving slabs on spacer
pads
➃ waterproof layer
➁ ROOFMATE SL-X
➄ screed to falls
➁ separating layer
(if required)
➅ roof outlet
➂ ROOFMATE SL-X
➂ separating layer (if
required)
➃ separating layer
(if required)
➄ waterproof layer
➅ concrete slab
➆ concrete slab
Figure 13 >> Ballasted inverted roof - insulation over internal
gutter
Figure 11 >> Ballasted inverted roof - outlet protected by paving
slabs
➇
➀
➁
➂
➃
➄
➀ paving slab on spacer pads
➅
➄ waterproof layer
➆
➁ separating layer (if required)
➂ ROOFMATE SL-X
➃ separating layer (if required)
➅ screed
➆ concrete slab
➇ flashing
Figure 14 >> Ballasted inverted roof - detail at eaves
STYROFOAM Solutions
21
Insulating ballasted inverted roofs: design considerations
Specification
J21 Mastic asphalt roofing
710 Inverted roof insulation
J41 Built-up felt roof coverings
710 Inverted roof insulation
J42 Single layer polymeric roof coverings
810 Inverted roof insulation
›››
Manufacturer and reference:
Dow Chemical Co. Ltd,
Building Solutions,
2 Heathrow Boulevard,
284 Bath Road, West Drayton, Middlesex, UB7 0DQ.
Tel: 020 8917 5050 - Fax: 020 8917 5413
ROOFMATE SL-X
Thickness†:
50/60/80/100/120/140/160/180/200mm
†delete as appropriate
Board size: 1250 x 600mm
Edge profile: shiplap
Design loading: 110kN/m2
Fire Classification: Reaction to fire:
BS EN 13164 Euroclass E
Working temperature range: -50°C to +75°C.
›››
do not lay insulation until roof is clear of other
subtrades.
›››
›››
›››
clean off all dirt and debris from base.
lay separation layer as required.
set out to minimise cutting and avoid small cut pieces
at perimeters and penetrations.
›››
loose lay boards, tightly butted and to brick pattern,
cut cleanly to fit closely around projections, upstands,
rainwater outlets, etc.
›››
on completion of laying ensure boards are in good
condition, with no springing, flexing or rocking.
Secure boards against wind uplift as soon as practicable.
Specify ballast layers with clauses 720, 730 or 731.
22
Insulating ballast inverted roofs: installation methods
Installation sequence
1.
Inspect the roof to ensure it is clean.
Plan the installation sequence and the layout of
ROOFMATE SL-X boards.
2.
Lay the separating layer (if required) over the
waterproof layer; lap all edges by 200 - 300mm,
at perimeters and penetrations turn up above the
installed thickness of the insulation.
3.
Lay ROOFMATE SL-X insulation boards in brick pattern
with shiplap edges pushed together firmly (Figure 15).
Figure 15
4.
Insulate upstands with ROOFMATE SL-X boards
(Figure 08).
5.
Fit ROOFMATE SL-X boards neatly around penetrations
(Figure 16). Cut boards with a sharp knife or fine
toothed saw.
6.
Lay the filter layer (if required) with 150mm laps or if
ROOFMATE MK 300mm laps at right angles to the
slope. Arrange laps to run down the slope (Figure 17).
At upstands and penetrations turn up the filter layer so
it finishes above the surface of the ballast.
7.
Lay paving slabs on supports around roof perimeters
Figure 16
and penetrations as required.
8.
Lay the ballast layer progressively. Work on an
advancing front away from the point of access so all
ballast material is carried across a protected
waterproof layer (Figure 18).
9.
Install cover flashings.
Key points
›››
careful setting out before installation begins will
minimise cutting and wastage.
›››
take care not to over-stress any area of the roof while
Figure 17
distributing the ballast.
›››
use scaffold boards when barrowing materials over
ROOFMATE SL-X boards.
Figure 18
STYROFOAM Solutions
23
Insulating lightweight inverted roofs: design considerations
General
U value
0.35
0.25
0.20
0.18
0.16
Lightweight inverted roofs are suitable for use with a wide
ROOFMATE LG-X
100
(includes 10mm thick mortar topping)
160
220*
260*
320*
range of waterproofing materials in both new and existing
Roof build-up:
buildings where limited roof top access is expected
ROOFMATE LG-X
(i.e. maintenance traffic only).
Separation layer
Mastic asphalt 20mm
The system is not suitable for use on heavily
Sand cement screed 50mm
trafficked areas, such as balconies and terraces, nor
Concrete deck 200mm
Rainwater cooling penalty calculated to BS EN ISO 6946 Annex D4
should it be used with loose-laid membranes.
* 2 layers required eg. 160mm ROOFMATE SL-X + 60mm ROOFMATE LG-X
➀
➁
➂
➃
➄
Table 14 Required ROOFMATE LG-X thickness (mm) to meet
U-values (W/m2.K)
Wind uplift
ROOFMATE LG-X boards are designed to minimise the
effect of wind uplift forces; the joints between boards are
➀ ROOFMATE LG-X
➁ separating layer (if
required)
➂ waterproof layer
➃ timber deck
➄ timber joist
Figure 19 >> Lightweight inverted roofs
interlocking, but not airtight, so differences in pressure
between the top and bottom surfaces of the boards produced by wind blowing across the roof - rapidly
equalise, reducing the uplift forces on the insulation.
When assessing the effect of wind uplift upon
STYROFOAM Solutions
ROOFMATE LG-X boards on a lightweight inverted roof it is
The STYROFOAM Solution for insulating lightweight
important to consider:
inverted roofs is ROOFMATE LG-X: it consists of
›››
predicted uplift force: predictions of wind uplift
STYROFOAM insulation boards with a factory applied top
should be based upon the calculation methods given
surface of modified mortar 10mm thick. The surface is
in BS 6339: Part 2.
mottled grey, resembling a cement:sand render with a
›››
means of attachment of the waterproof layer:
wood float finish.
waterproof layers on lightweight inverted roofs may
ROOFMATE LG-X is designed to give the maximum benefit
be partially or fully adhered or mechanically attached:
in lightweight inverted roofs; the boards are:
the weight of ROOFMATE LG-X boards should be
›››
they lock together to give a continuous insulation
layer, eliminating thermal bridging and reducing the
effect of wind uplift.
›››
›››
›››
ignored when assessing the stability of the waterproof
tongued and grooved on their long edges to ensure
light enough for one man to handle.
can be cut and shaped on site with a masonry saw.
installed in one easy operation, avoiding the cost of a
ballast layer.
Consult Page 08 for the full physical properties and
performance characteristics of ROOFMATE LG-X boards.
24
layer under windload.
›››
laying pattern of boards: ROOFMATE LG-X boards
must be laid in brick pattern with their tongued and
grooved edges fully interlocked.
Insulating lightweight inverted roofs: design considerations
›››
parapets and roof kerbs: at roof perimeters
➀
ROOFMATE LG-X boards must be protected from wind
blowing directly underneath the boards: kerbs should
➁
➂
➃
➅
➄
extend at least 50mm above the top of the boards.
➆
On roofs with low wind exposure ROOFMATE LG-X
boards may be laid to drain directly into an edge
➇
gutter. Protect the board edge with a cover flashing
(Figure 20).
›››
edge restraint: the mortar topping to the
ROOFMATE LG-X boards provides some resistance to
uplift, but edge restraint is usually required at the roof
perimeter and around large penetrations such as plant
rooms. Edge restraint can be achieved by laying a
single row of 50mm thick paving slabs or adhering the
boards to the substrate with a suitable adhesive eg.
➀ paving slab
➄ flashing
➁ ROOFMATE LG-X
➅ screed to falls
➂ separating layer
(if required)
➆ concrete slab
➃ waterproof layer
➇ WALLMATE CW-X
Figure 20 >> Lightweight inverted roof- detail at eaves
Tixophalte*. If exceptionally high uplift forces are
involved further rows of paving or possibly mechanical
restraint will be required.
A ROOFMATE LG-X project assessment form is provided on
page 34 of this brochure: the specifier should send a
➀
completed copy of the form to Dow for each project
designed with ROOFMATE LG-X: on the basis of project
➁
information supplied Dow will calculate the amount and
location of restraint required. For assistance in completing
the form please contact Dow.
➂
➃
➄
➅
➆
➄
Edge details
Waterproof upstands should be protected by fitting
ROOFMATE LG-X boards against the upstands and covering
➇
them with an apron flashing (Figure 21). Extending the
➈
insulation in this way also helps to avoid thermal bridging.
Any apron flashing should terminate at least 150mm above
➀ apron flashing
the top of the boards.
➁ ROOFMATE LG-X
➂ paving slab
➃ ROOFMATE LG-X
➈ WALLMATE CW-X
➄ separating layer
(if required)
➅ waterproof layer
➆ screed to falls
➇ concrete slab
➈ WALLMATE CW-X
Figure 21 >> Lightweight inverted roof - detail at upstand
*
available from Callenders Ltd. tel 01268 591155
STYROFOAM Solutions
25
Insulating lightweight inverted roofs: design considerations
Drains and gutters
Specification
Gratings for rainwater outlets may be raised on spacer rings
J41 Built-up felt roof coverings
710 Inverted roof insulation
to reduce the risk of blockage; cut a hole in the ROOFMATE
J41 Built-up felt roof coverings
LG-X board to accommodate the outlet.
810 Inverted roof insulation
Alternatively, a paving slab supported on spacer pads may
J42 Single layer polymeric roof coverings
be used above a flat grating (Figure 22).
810 Inverted roof insulation
›››
Manufacturer and reference:
Dow Chemical Co. Ltd,
Building Solutions,
➀
2 Heathrow Boulevard,
➁
➂
➃
➄
284 Bath Road, West Drayton, Middlesex, UB7 0DQ.
Tel: 020 8917 5050 - Fax: 020 8917 5413
➅
➆
ROOFMATE LG-X
Roofs for maintenance traffic
Thickness†: 60/70/90/110/130†† mm
➀ paving slab on spacer
pads
➃ waterproof layer
(including 10mm mortar topping)
➁ ROOFMATE LG-X
➄ screed to falls
➅ concrete slab
†delete as appropriate
➂ separating layer
(if required)
††thicker products available on request up to 190 mm
➆ rainwater outlet
Board size: 1200 x 600mm
Figure 22 >> Lightweight inverted roof - detail at outlet
Edge profile: tongued and grooved on long sides,
butt edged on short sides.
Design loading: 110kN/m2
Fire Classification: Reaction to fire:
BS EN 13164 Euroclass E (insulation only)
Working temperature range: -50°C to +75°C.
›››
do not lay insulation until roof is clear of other
subtrades.
›››
›››
clean off all dirt and debris from base.
set out to minimise cutting and avoid small cut pieces
at perimeters and penetrations.
›››
loose lay boards, tightly butted and to brick pattern,
cut cleanly to fit closely around projections, upstands,
rainwater outlets, etc.
›››
on completion of laying ensure boards are in good
condition, with no springing, flexing or rocking.
Secure boards against wind uplift as soon as
practicable.
26
Insulating lightweight inverted roofs: installation methods
Installation sequence
Key points
1.
›››
Inspect the roof to ensure it is clean. Plan the
installation sequence and the layout of
ROOFMATE LG-X boards.
2.
minimise cutting and wastage.
›››
Lay the separating layer (if required) over the
waterproof layer; lap all edges by 200 - 300mm, at the
3.
›››
keep the waterproof layer clear of debris throughout
installation.
›››
protect ROOFMATE LG-X boards from damage by
Plan and set out ROOFMATE LG-X boards with 3 - 5mm
subsequent construction activity: replace any
between adjacent boards and between boards and
damaged boards.
upstands, kerbs and penetrations.
4.
when placing pallet loads of ROOFMATE LG-X onto the
roof, distribute them to prevent overloading.
perimeters and penetrations turn up above the
installed thickness of the insulation.
careful setting out before installation begins will
Start laying the first row of boards with their long
›››
do not store unrestrained ROOFMATE LG-X boards on
the roof.
edge against the longest side of the roof. If there is an
5.
6.
angle fillet chamfer the board edges to get a good fit.
Mortar topping
Do not use cut pieces of less than half board length at
As with most mortar coatings, hairline cracks may develop
the perimeter: they may be used towards the roof
in the mortar topping of ROOFMATE LG-X boards; such
centre.
cracks will have no effect upon the performance of the
Lay the second row of boards, staggered by half a
product. They will not propagate, but will tend to heal as
board length, ensure the tongued and grooved edges
hydration of the cement continues.
interlock.
7.
Stagger subsequent rows by half board lengths
(Figure 23).
8.
Accidental damage to the topping of ROOFMATE LG-X
boards can be repaired in-situ using a suitable latexmodified cement.
At penetrations cut the board across its width at the
line of the penetration and neatly cut a shaped recess
in each part so the edges of the ROOFMATE LG-X
boards still interlock.
9.
At changes in roof slope use a masonry saw to cut the
mortar topping of the ROOFMATE LG-X boards along
the line of change of plane. This will reduce cracking
as the STYROFOAM insulation flexes under load.
Leave the saw cut open.
10. Place the specified edge restraint along the roof
perimeter and around large penetrations.
11. Install cover flashings.
Figure 23
STYROFOAM Solutions
27
Insulating green roofs: design considerations
General
STYROFOAM Solutions
Flat roofs of suitable construction may be used to provide
The STYROFOAM Solution for insulating green roofs is
planted or landscaped areas which can offer a valuable
ROOFMATE SL-X.
amenity within the built environment. Such 'green' roofs
can enhance the appearance of the building and provide
additional outdoor facilities for building users.
ROOFMATE SL-X is designed to give the maximum benefit
in inverted roof construction; it is:
›››
An inverted roof with ROOFMATE insulation is the ideal
solution for 'green' roofs where landscaping or planting is
rot proof - performance unaffected by conditions
below the plant-bearing layer.
›››
available in a range of thicknesses from 50mm to
provided. The insulation boards protect the waterproof
200mm allow thermal performance to be matched to
layer and the planting provides necessary ballast
project requirements.
›››
(Figures 24 and 25).
made with shiplapped edges to ensure a good
interlock between boards, preventing thermal
bridging.
➀
➁
➂
➃
➄
➅
➀ planting / drainage
layer (50-150mm)
➃ separating layer
(if required)
➁ filter layer
➄ waterproof layer
➂ ROOFMATE SL-X
➅ concrete slab
Consult Page 08 for the full physical properties and
performance characteristics of ROOFMATE SL-X.
Waterproof layers
Suitable waterproof layers for green roof constructions
include:
›››
›››
mastic asphalt.
modified bitumen membranes.
Figure 24 >> Extensive green roof
The ROOFMATE SL-X boards will help protect the
waterproof layer from root penetration: consult the
membrane manufacturer for information on suitability and
➀
➁
➂
➄
➅
➆
➇
➀ planting layer
(150-500mm)
➄ ROOFMATE SL-X
➁ filter layer
➅ separating layer
(if required)
➂ drainage layer
➆ waterproof layer
➃ filter layer
➇ concrete slab
Figure 25 >> Intensive green roof
28
protection.
Insulating green roofs: design considerations
Filter layers
Specification
Filter layers will be required above the drainage layer and
J21 Mastic asphalt roofing
the insulation to prevent fines being washed down to the
drainage and waterproof layers. Suitable materials include
geotextiles with minimum weight of
140g/m2,
710 Inverted roof insulation
J41 Built-up felt roof coverings
710 Inverted roof insulation
such as
ROOFSTAT R.
J42 Single layer polymeric roof coverings
810 Inverted roof insulation
Planting
›››
Manufacturer and reference:
The planting on a green roof may be:
Dow Chemical Co. Ltd,
›››
extensive: using a thin plant-bearing layer
Building Solutions,
(50-150mm) and hardy plants such as sedums and
2 Heathrow Boulevard,
grasses. Extensive green roofs are not usually intended
284 Bath Road, West Drayton, Middlesex, UB7 0DQ.
for access. Once the planting is established - which
Tel: 020 8917 5050 - Fax: 020 8917 5413
may take only a few months - it requires very little
›››
maintenance (Figure 24).
ROOFMATE SL-X
intensive: using a thick plant-bearing layer
Thickness†:
(150-500mm) and traditional garden plants including
50/60/75/80/90/100/120/140/160/180/200mm
lawn-grass, shrubs and even small trees. Intensive
†delete
green roofs require full access for maintenance, are
Board size: 1250 x 600mm
suitable for roof gardens and are often combined with
Edge profile: shiplap
paved areas and terraces to provide amenity areas.
Design loading: 110kN/m2
The type of planting chosen will determine the roof
Fire Classification: Reaction to fire:
construction above the filter layer: extensive planting
BS EN 13164 Euroclass E
requires a planting layer which will retain some water
Working temperature range: -50°C to +75°C.
as appropriate
whilst intensive planting requires a thicker, soil-based
plant-bearing layer and a drainage layer (Figure 25).
›››
do not lay insulation until roof is clear of other
subtrades.
Loading
›››
›››
The load imposed by saturated soil can be as high as
25kg/m2 per 10mm depth, and that of the gravel drainage
clean off all dirt and debris from base.
set out to minimise cutting and avoid small cut pieces
at perimeters and penetrations.
›››
loose lay boards, tightly butted and to brick pattern,
layer 16kg/m2 per 10mm depth. A further load of 20kg/m2
cut cleanly to fit closely around projections, upstands,
should be allowed for water logging of the gravel drainage
rainwater outlets, etc.
layer (minimum 50mm depth).
›››
on completion of laying ensure boards are in good
condition, with no springing, flexing or rocking.
Secure boards against wind uplift as soon as
practicable.
Specify the green roof covering with clause 770.
STYROFOAM Solutions
29
Insulating green roofs: installation methods
Installation sequence
1.
Inspect the roof to ensure it is clean. Plan the
installation sequence and the layout of
ROOFMATE SL-X boards.
2.
Lay the separating layer (if required) over the
waterproof layer; lap all edges by 200 - 300mm, at
perimeters and penetrations turn up above the
installed thickness of the insulation.
3.
Lay ROOFMATE SL-X insulation boards in brick pattern
with shiplap edges pushed together firmly.
4.
Insulate upstands with ROOFMATE SL-X boards.
5.
Fit ROOFMATE SL-X boards neatly around penetrations.
Cut boards with a sharp knife or fine toothed saw.
6.
Lay the filter layer with 150mm laps at right angles to
the slope. Arrange laps to run down the slope.
Turn up the filter layer at upstands and penetrations.
7.
Proceed with drainage layer, (50mm deep gravel
graded 20 - 30mm) soil and planting, taking care not
to disturb the ROOFMATE SL-X boards and filter layer.
Key points
›››
careful setting out before installation begins will
minimise cutting and wastage.
›››
work on an advancing front away from the point of
access so all loading material is carried across a
protected waterproof layer.
›››
take care not to over-stress any area of the roof while
distributing the soil layer.
›››
use scaffold boards when wheel barrowing materials
over ROOFMATE SL-X boards.
30
Inverted roofs for renovation projects: design considerations
General
The STYROFOAM Solutions for the renovation of flat
The inverted roof concept can be used to upgrade the
roofs are ROOFMATE SL-X and ROOFMATE LG-X.
insulation level of an existing roof without the need to
ROOFMATE SL-X is designed to give the maximum benefit
remove and renew the existing waterproof layer, subject to
in ballasted inverted roof construction:-
certain conditions:
›››
the structure must be capable of carrying the
›››
50-200mm allows thermal performance to be
additional load.
›››
›››
matched to project requirements
the existing waterproof layer must be sound.
adequate falls and drainage outlets must be in place.
a range of thicknesses from
(see Table 06 on Page 14).
›››
shiplapped edges ensure a good interlock between
boards, which helps prevent thermal bridging.
Adopting the inverted roof systems allows work to
›››
rigid boards provide a firm base for the ballast layer.
continue without interruption and with no need to disturb
the building interior.
ROOFMATE LG-X consists of STYROFOAM insulation boards
Both the ballasted inverted roof and the lightweight
with a factory applied top surface of modified mortar
solutions are suitable for renovation projects: the choice of
10mm thick. The surface is mottled grey, resembling a
solution will depend upon the loadbearing capacity of the
cement:sand render with a wood float finish.
roof structure and other project requirements.
ROOFMATE LG-X is designed to give the maximum benefit
Always obtain the advice of a roofing specialist, who
in lightweight inverted roofs; the boards are:
should inspect the existing roof to confirm:
›››
›››
›››
›››
›››
›››
›››
tongued and grooved on their long edges to ensure
drainage.
they lock together to give a continuous insulation
falls.
layer, reducing the effect of wind uplift and
outlets.
eliminating thermal bridging.
waterproof layer.
›››
and shaped on site with a masonry saw.
details.
penetrations.
light enough for one man to handle and can be cut
›››
installed in one easy operation, avoiding the cost of a
ballast layer.
Consult Page 08 for the full physical and performance
properties of ROOFMATE SL-X and ROOFMATE LG-X.
Loading
Ensure the existing structure is able to support the
additional load imposed by the insulation and/or
loading layer; those additional loads are:
›››
›››
minimum 100kg/m2 for a ballasted solution.
minimum 30kg/m2 for a lightweight solution.
STYROFOAM Solutions
31
Inverted roofs for renovation projects: design considerations
Waterproof layer
Edge details
The condition of the waterproof layer must be checked.
Upgrading an existing roof by the addition of ROOFMATE
Whilst ROOFMATE boards will protect an existing layer, and
insulation will raise the finished surface level by the
thus increase its life expectancy, they are not a cure for
combined thickness of the insulation and any ballast layer.
failure of the waterproof layer.
Parapets, abutments, penetrations and flashings should be
Localised defects in a waterproof layer, which
otherwise is in good condition, must be repaired.
modified to ensure the roof is adequately contained and
weatherproof. The edges of ROOFMATE LG-X boards must
be protected from sunlight and detailing must prevent
A waterproof layer which is near the end of its useful life
wind blowing directly under the boards (Figure 26).
may be overlaid with a new waterproof layer. Where a roof
has no drainage falls the waterproof layer should be to a
tanking specification.
For renovation projects using ROOFMATE LG insulation, the
flashing need only extend 50mm above the top surface of
the boards, so long as a 50mm, aggregate filled, gap is left
Small penetrations such as screed vents and cable ducts
between the boards and the perimeter (Figure 27).
require careful detailing: it may be preferable to eliminate
many existing features and make good the waterproofing
➀
➁
➂
➃
➄
locally.
Existing bitumen felt may have a bonded covering of stone
chippings. Before overlaying with ROOFMATE boards
➅
➆
➇
sweep off all loose chippings and lay a cushioning layer,
such as ETHAFOAM* 222E.
➈
Interstitial moisture
➀ flashing
➅ ROOFMATE SL-X
Typically a heavyweight roof being considered for
➁ waterproof layer
renovation will have little or no insulation above the
➂ timber kerb
➆ separating layer
(if required)
concrete slab, and no VCL below the slab. Consequently,
➃ ballast
there is a high probability of condensation occurring at the
interface of the concrete and the waterproof layer during
➄ separating layer
(if required)
➇ waterproof layer
➈ existing slab
Figure 26 >> Renovated inverted roof - detail at kerb
the winter. The build up of water in the top of the concrete
may be increased by any leakage through defects in the
waterproof layer, in which case the summer 'dry-out' of
➀
➁
condensation will be insufficient to remove moisture from
the concrete, resulting in a permanently waterlogged slab.
➂
The installation of an inverted roof system, in conjunction
➃
➄
➅
with any remedial treatment necessary for the waterproof
layer, will substantially reduce the risk of condensation and
➆
allow the slab to dry out.
Using an inverted roof, any insulation already in the roof
construction beneath the waterproofing layer should be
➀ flashing
removed to avoid the risk of internal condensation. If in
➁ ballast
doubt carry out a Condensation Risk Analysis.
➂ paving slab
➃ ROOFMATE LG-X
➄ separating layer
(if required)
➅ waterproof layer
➆ existing slab
Figure 27 >> Renovated inverted roof - detail at upstand
* Trademark of The Dow Chemical Company
32
Inverted roofs for renovation projects: design considerations
Drainage
Rainwater outlets must be capable of receiving run-off
from the top of the insulation and from the waterproof
layer.
If existing falls are inadequate:
›››
remove waterproof layer, lay screed to falls, provide
new waterproof layer.
›››
remove waterproof layer and replace with new to a
tanking specification.
›››
install additional rainwater outlets at the low points.
ROOFMATE boards should not be installed where they
will be submerged in ponded water.
Specification
Specifications for renovation projects will be similar to
those for new build projects, but may need to include
clauses to:
›››
›››
›››
›››
provide a drainage fall to the roof.
repair or replace waterproof layer.
extend shallow roof kerbs.
install additional rainwater outlets in areas where
water ponds.
›››
›››
modify gratings or rainwater outlets.
level out large depressions in the substrate and repair
the waterproof layer.
Maintenance
All roofs should be inspected as part of normal
maintenance procedures. Inspections should cover the
waterproof layer, outlets, gutters, flashings and detail work.
The inspection should confirm that neither the insulation
nor ballast has been displaced, particular care should be
taken with ROOFMATE LG-X.
In some environments there may be weed growth on the
roof. Whilst this is unlikely to damage an inverted roof it is
advisable to eradicate weed growth by removing it or by
using a suitable water-based weed killer. Check its
compatibility with STYROFOAM before use.
STYROFOAM Solutions
33
ROOFMATE LG-X Project assessment sheet
Fax Number: 020 8917 5413
Information supplied by:
Date:
Project data
• Project name:
• Site address: (including Post Code)
• Specifiers name:
Address:
Contact name:
Telephone number:
Fax number:
• Area of ROOFMATE LG-X:
• Thickness of ROOFMATE LG-X:
• Type of waterproofing:
• Roofer’s name:
Address:
Contact name:
Telephone number:
Fax number:
• Date to be roofed:
Roof details
• Please provide a complete roof plan:
• Roof height:
• Parapet height:
Roof width:
Roof length:
Parapet width:
• Is the roof slope less than 5 degrees?
• Are there any steps or changes in the roof surface?
• Is there a plant room or any other structure on the roof - if so provide details?
• Will ROOFMATE LG-X boards (and paving slabs if required) be concealed by a parapet/kerb along all edges?
Give details:
34
Insulating floors: basic principles
This section describes the thermal insulation of floors using
By including in the floor construction a layer of thermal
STYROFOAM extruded polystyrene insulation from Dow.
insulation continuous with that in the rest of the building
It covers the principles, design considerations and
envelope, heat loss is reduced and thermal bridges at the
installation methods for groundbearing and suspended
junction of the floors and walls are avoided. However,
floors in new build and renovation projects.
thermal insulation incorporated in a floor must not
compromise any of the functional requirements.
STYROFOAM Solutions
The STYROFOAM Solution for insulating
groundbearing and suspended floors in new build and
Agrément Certificate 92/2782 covers the use of
FLOORMATE 200-X, STYROFOAM SP-X and FLOORMATE
500-X in groundbearing floors.
renovation is FLOORMATE which includes the
products: FLOORMATE 200-X, STYROFOAM SP-X,
➀
➁
➂
➃
FLOORMATE 500-X and FLOORMATE 700-A.
Insulating floors
➄
Floors are classified as:
›››
➅
ground floors, in contact directly, or indirectly with
➆
ground.
›››
exposed floors, forming lowest part of structure over
un-enclosed airspace (e.g. balcony).
›››
semi-exposed floors, lowest part of a structure over an
enclosed but unheated space (e.g. a floor over a
➀ screed with light mesh
➁ vapour control layer
(VCL)
➂ FLOORMATE
intermediate floors, having heated space above and
membrane (DPM)
➄ concrete slab
➅ hardcore with sand
blinding
➆ ground
garage).
›››
➃ damp proof
reinforcement
Figure 28 >> Groundbearing floor slab
below.
Ground floors may be groundbearing (figure 28) or
➀
➁
➂
suspended (figure 29): all other floors are, by definition,
suspended.
➃
The ground absorbs heat from floors close to or in contact
with it, with high soil moisture content increasing the rate
of loss. Those effects, when combined with the natural
temperature gradient in buildings, can lead to
uncomfortable internal environments, condensation at
➀ board or screed finish
➁ VCL/slip sheet (SS) 500
gauge polyethylene
➂ FLOORMATE
➃ beam and block floor
with levelling topping
wall/floor junctions and higher than predicted energy
usage. Exposed and semi-exposed floors, suffer heat loss to
Figure 29 >> Suspended beam and block floor
air, in the same wayother building elements.
STYROFOAM Solutions
35
Insulating floors: basic principles
Determining the floor construction
Loadings
Floors must be designed as a whole element taking
Floors should be designed to sustain safely the combined
account of all the functional requirements. The position of
dead and imposed loads, without excessive deflection
the insulation is influenced by the type of construction, the
(Building Regulations 1991: Schedule 1 Requirement A1:
predicted floor loading and the heating regime.
Standard 1.1 in Scotland).
Buildings which are to be intermittently heated are usually
In self-contained dwellings FLOORMATE insulation can
designed with ‘fast response’ fabric with the thermal
support the design load when:
insulation on the inside of the structure. Heating systems
›››
which utilise the structure as a heat store require the
thermal insulation to encompass as much of the structure
sited above a groundbearing slab and covered with
suitable plywood, chipboard or screed.
›››
sited below a groundbearing slab and receiving the
as possible.
dead load of the slab and the loading transferred
The design of foundations and groundbearing floors is
through the slab.
influenced by the site on which the building is to be
constructed. The load bearing capacity of the soil should
›››
laid on timber decking and covered with suitable
plywood or chipboard.
be established before design work is undertaken.
Whilst a groundbearing floor is usually an effective
construction for domestic and commercial buildings,
a ground floor should be suspended in the following
Load bearing internal partitions must be built off the
structural floor not the FLOORMATE insulation boards.
Internal masonry walls must have their own foundations.
circumstances:
For buildings other than dwellings the correct grade of
›››
FLOORMATE insulation should be selected on the basis of
domestic buildings on sloping sites where more than
600mm depth of infill would be required.
›››
›››
an assessment of the loading by a structural engineer.
where the bearing capacity and nature of the ground
The maximum acceptable load on FLOORMATE insulation
varies from one part to another.
products is the design load together with a suitable safety
where the ground is of shrinkable clay, expansive
factor. (The “design load” is that load on the insulation
material or other unstable soil type.
which will give a maximum compression of 2% after 50
years)
The site should be assessed for hazards likely to affect
In the unlikely event of floor loadings being too high for an
substructure and groundbearing floors such as chemicals
available grade of FLOORMATE board the material may be
(particularly sulphates), contaminated material above or in
used as vertical edge insulation, which is not subject to
the ground and waterlogged ground. In some parts of the
loadings from the floor slab.
UK special precautions are necessary to reduce the entry of
radon gas, details of those geographical areas may be
obtained from the Department for Environment, Food and
Rural Affairs (DEFRA).
Floors must be resistant to ground hazards as outlined in
Building Regulations C1 + C2 (Standard 3.1 - 3.4 in Scotland).
36
Insulating floors: basic principles
Thermal performance
Table 15 gives the thicknesses of FLOORMATE 200–X
required to achieve a range of U-values for ground floors.
Refer to BS EN ISO 6946, BS EN 13370, CIBSE Guide A and
BRE BR 443 ‘Conventions for U-value calculations’ for the
method of U-value calculation.
Heat loss from floors is concentrated at the perimeter.
Whilst an uninsulated ground floor may achieve the
required U-value the use of edge insulation will avoid
thermal bridging at the floor perimeter. FLOORMATE
boards may be installed as vertical or horizontal edge
insulation depending on the application.When used as
vertical edge insulation, FLOORMATE may be placed on the
inside of the external walls (see figure 30), within a cavity or
on the outside of the walls. Where horizontal edge insulaFigure 30 >> Horizontal edge insulation below concrete slab
tion is used beneath the slab maintain the minimum slab
thickness by setting the FLOORMATE boards into the sand
blinding or by increasing the overall depth of the slab.
Refer also to BRE document BR 262 ‘Thermal insulation:
avoiding risks’ and DEFRA/DTLR ‘Robust Details’.
Solid ground bearing floor
P/A
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.90
1.00
0.18
25
70
90
110
110
120
120
140
140
140
0.20
25
60
80
90
100
110
110
110
120
120
0.22
-
40
70
80
90
90
100
100
100
110
0.25
-
30
50
60
70
80
80
80
90
90
0.21
0.36
0.48
0.58
0.67
0.75
0.82
0.89
0.95
1.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.90
1.00
0.18
50
90
110
120
120
120
140
140
140
140
0.20
30
80
90
100
100
110
110
110
110
120
0.22
25
60
80
90
90
90
100
100
100
100
0.25
25
50
60
70
80
80
80
80
90
90
0.26
0.41
0.52
0.61
0.68
0.74
0.79
0.83
0.87
0.90
U-values
No insulation
65mm Screed
Suspended beam & block floor
P/A
U-values
No insulation
65mm Screed; block 100 x 440mm, (0.51 W/mK); beam 60mm, (1.13 W/mK)
Table 15 Thickness of FLOORMATE 200-X (mm) to meet U-values (W/m2.K)
STYROFOAM Solutions
37
Insulating groundbearing floors: design
General description
➀
➁
➂
➃
In a groundbearing floor the ground is used to support the
floor slab for the life of the building. The floor slab is
formed:
➄
›››
➅
with reinforced or non-reinforced concrete poured
➆
within, but separate from the external walls, which are
built off separate foundations.
›››
as a reinforced concrete raft combining both
foundation and floor.
➀ floor finish e.g. carpet
➁ timber board
➂ Vapour control layer
(VCL)/Slip sheet (SS)
➄ concrete slab
➅ Damp proof
membrane (DPM)
➆ hardcore with sand
blinding
➃ FLOORMATE
The FLOORMATE insulation can be installed:
›››
›››
›››
Figure 31 >> Insulation between the slab and a board finish
between the slab and a board finish (figure 31).
between the slab and the screed (figure 32).
➀
below the slab (figure 33).
➁
Positioning FLOORMATE insulation below the slab avoids
➂
➃
any disruption to the construction sequence. In this
➄
position it supports the floor slab and it is essential the
➅
insulation have sufficient compressive strength: it must also
be placed on well compacted level surface to avoid
uneven settlement.
➆
➀ floor finish e.g. carpet
➁ screed with heating
elements
Because of the difficulty of providing edge insulation to a
➂ VCL
raft foundation, FLOORMATE insulation is not normally
installed below the slab in raft constructions (figure 34).
➃
➄
➅
➆
FLOORMATE
concrete slab
DPM
hardcore with sand
blinding
Figure 32 >> Insulation between the slab and the screed
FLOORMATE insulation is designed to give the maximum
benefit in groundbearing floor construction:
›››
➀
a range of compressive strengths to match loading
➁
conditions.
›››
›››
resistant to ground moisture.
➂
thicknesses from 25mm to 100mm allow thermal
➃
➄
performance to be matched to project requirements.
➅
Refer to Page 08 for the full physical and performance
properties of FLOORMATE products.
➀ floor finish e.g. carpet
➁ screed
➂ concrete slab
➃ DPM
➄ FLOORMATE
➅ hardcore with sand
incorporating heating
elements
Figure 33 >> Insulation below the slab
38
blinding
Insulating groundbearing floors: design
If FLOORMATE boards are to be installed over a slab the
surface must be even (no more than 5mm deviation under
a 3m straight edge) to prevent excessive deflection of the
finished floor (refer to Agrément certificate 92/2782,
BS 8203 and BS 8204: Part 1). FLOORMATE boards should
only be laid over a slab once the building is weather tight
and should be overlaid as soon as practicable to avoid
damage from follow-on trades.
Screeds
Screeds must neither breakdown nor permit indentation of
the floor finish.
Screeds which are not monolithic with the slab should be
at least 65mm thick (75mm if heated or subject to higher
Figure 34 >> Insulation applied over a concrete raft
loadings) to prevent cracking and curling. They should
incorporate a light mesh (D49 to BS 4483) centrally
Site preparation
positioned and passing through any joints in the screed.
A bearing surface for the concrete slab should be prepared
An unbonded screed laid over FLOORMATE boards should
by removing all topsoil and vegetable matter and making
be separated from the insulation by a slipsheet of 500
up the level to the required height with inert, well graded
gauge polyethylene, well lapped and turned up at the floor
fill. The fill, which should pass a 150mm by 100mm screen,
edges. Floating screeds must not bridge gaps in the layer
should be laid and compacted in layers not exceeding
below.
225mm to finished depths from 100mm to 600mm. Greater
depths may be used for buildings other than dwellings in
some circumstances.
Once laid, screeds should be covered immediately with a
polyethylene sheet to ensure a slow cure and help avoid
shrinkage cracks: the covering should be left in place for
The fill should be blinded with the minimum thickness
seven days (BRE Defect Action Sheet 52).
necessary to give a suitable surface for the next layer of the
construction and to protect it from being damaged by the
hard core. Sand blinding is the most suitable to receive a
sheet damp proof membrane (DPM) or FLOORMATE
boards. Blinding to receive FLOORMATE boards should be
flat and level so the boards can be laid accurately in a
continuous layer without ‘kicking up’ or rocking.
Concrete slabs
Concrete slabs should be at least 100mm thick; the need
for increased thickness and for reinforcement should be
assessed in accordance with BS 8110: Pt 1. Movement
joints in the slab should be aligned with movement joints
Where screeds are heated extra care must be taken on site
to avoid failure of the heating elements and cracking of the
screed. Electric heating elements may need to be
separated from FLOORMATE products by a thickness of
screed; check with the heating system manufacturer before
specifying.
Curing/drying
Sufficient time should be allowed for the curing and drying
out of concrete slabs and screeds. Guidance is given in
BRE publication: ‘Floors and Flooring’ (Table1.3) and
BS 8203.
in other elements in the structure. A slip sheet (SS) (which
may be the DPM) must be incorporated between poured
concrete and FLOORMATE insulation.
STYROFOAM Solutions
39
Insulating groundbearing floors: design
Thermal bridging
To avoid a thermal bridge at the wall/ floor junction
continue wall insulation down to the bottom of the
➀
concrete slab and install 25mm of FLOORMATE insulation
➁
➂
➃
➄
vertically between the edge of the slab and the inner leaf.
The exposed edge of the FLOORMATE board will normally
➇
➅
be hidden by the internal plaster and skirting but at
thresholds should be protected with a timber board.
➆
Alternatively, insulating blocks may be used for the inner
➀
➁
➂
➃
➄
leaf of the wall below floor level.
Doors in external walls require openings at floor level
which need special attention to avoid thermal bridges
(figures 35 to 37). Refer also to BRE document ‘Thermal
insulation: avoiding risks’ and DEFRA/DTLR ‘Robust Details’.
WALLMATE CW-X
floor finish
VCL/SS
FLOORMATE
DPM
➅ concrete slab
➆ hardcore with sand
blinding
➇ Damp proof course
(DPC)
Figure 35 >> FLOORMATE boards above slab junction with
WALLMATE CW-X
Moisture
Building Regulation C2 (Standard 3.4 in Scotland) requires
floors to resist the passage of ground moisture into the
➀
➁
➂
➃
building. Moisture can reach the interior of the building as
either ground water rising through porous construction
elements or construction water from concrete slabs or
➆
➄
screeds. Specific guidance is given in Approved
document C (Technical Handbook section 3.4 - Scotland).
A DPM placed above the slab and linked to the damp
proof course (DPC) will exclude ground moisture and
protect the finish against construction moisture. The
vapour control layer (VCL) must be positioned on the
warm side of the insulation.
➅
➀
➁
➂
➃
floor finish
VCL/SS
FLOORMATE
DPM
➄ concrete slab
➅ hardcore with sand
blinding
➆ DPC
Figure 36 >> FLOORMATE boards above slab junction with
STYROFOAM
If the DPM is positioned below the slab a separate moisture
barrier must be included above the slab to protect any
moisture sensitive floor finishes; this additional moisture
➀
barrier will also assist the proper curing of the concrete.
➁
When laying FLOORMATE boards over liquid applied DPMs
➂
ensure the DPM does not contain solvents incompatible
➃
➄
with extruded polystyrene foam. Check with the DPM
manufacturer.
➅
➀ threshold
➁ DPC
➂ concrete slab
➃ DPM
➄ FLOORMATE
➅ hardcore with sand
blinding
Figure 37 >> Avoiding thermal bridges at thresholds, typical
solution
40
Insulating groundbearing floors: design
Surface water arising from conditions of use, e.g. water
kitchens and bathrooms can damage some flooring or
➀
➁
➂
➃
flooring panels such as chipboard. Where surface water is
➄
likely to occur moisture resistant products or grades of
➅
carried on footwear into entrance halls or spillages in
product should be used throughout the floor construction.
FLOORMATE insulation is resistant to moisture.
➀ floor finish
➁ access cover
➂ services
Services
Services such as gas and central heating pipes and
➃ pre-formed channel
set into screed
➄ VCL
➅ FLOORMATE
Figure 38 >> Typical service run in floor screed
electrical cables should be run in a duct set into the screed
or the FLOORMATE boards to allow for access (figure 38).
Overlaying FLOORMATE with timber
Services should not be embedded:
As FLOORMATE boards do not provide a suitable surface for
›››
faults are hard to find, and repair requires the floor
the direct application of a floor finish: they must be
finish to be taken up and the screed to be broken up,
overlaid with a screed or with a timber based board.
possibly damaging other services.
When FLOORMATE insulation is overlaid with a board, there
the thickness of the screed is reduced over the service,
is a risk of the insulation being compressed where the floor
increasing the risk of cracking.
is subjected to relatively high loads for extended periods,
›››
possibly leading to uneven floor surfaces. Check design
Electrical cables less than 50mm from the underside of the
load to ensure use of the correct FLOORMATE grade.
flooring panels should be protected from the floor panel’s
fixings by an earthed metallic sheath or earthed steel
conduit.
Before laying FLOORMATE boards battens should be
positioned at doorways and the foot of stairs and to
support partitions, kitchen fittings and sanitary fittings
PVC-covered cables likely to come into contact with
(figure 39). The battens should be preservative treated, in
FLOORMATE insulation should be protected by metal
accordance with BS 5268: Part 5 (check compatibility of
or uPVC conduit or trunking to avoid the risk of
preservatives with FLOORMATE insulation), and fixed to the
plasticiser migration from the PVC.
slab through the DPM. (Adequate time should be allowed
Water service pipes rising through a ground floor must be
for preservatives to fix and for solvents from solvent based
adequately insulated to prevent freezing (for guidance
preservatives to evaporate.)
consult BRE document ‘Thermal insulation: avoiding risks’).
To avoid dampness entering the building the DPM must be
sealed around pipes and ducts where they pass through
the floor construction.
➀
Underfloor heating systems
increase, for guidance refer to BS EN 1264-4: 2001 and the
➁
➂
➃
➄
Domestic Heating Compliance Guide.
➅
The use of warm water underfloor heating is on the
➀ door opening
➁ VCL/SS
➂ timber batten
➃ FLOORMATE
➄ DPM
➅ floor slab
Figure 39 >> Additional support at thresholds
STYROFOAM Solutions
41
Insulating groundbearing floors: design
Moisture resistant overlays and finishes should only be
Specification
placed once the building is weathertight. They must be
The following NBS clauses are relevant to the specification
protected from damage by residual moisture in screeds
of FLOORMATE insulation:
and slabs. A slipsheet (500 gauge polyethylene) should
E20 Formwork for in situ concrete
always be laid between FLOORMATE boards and the floor
covering. A construction which is still damp when
FLOORMATE insulation and a boarded finish are to be
200 Underslab sheet insulation
›››
›››
installed should be overlaid with an additional DPM of at
least 1200 gauge polyethylene, well lapped, sealed at joints
Insulation: extruded polystyrene boards
Thickness: 25/30/35/40/50/60/
70/75/80/90/100/120/140†mm
›››
Manufacturer and reference:
and turned up at edges behind skirting to protect the
Dow Chemical Co. Ltd,
flooring from construction moisture in the wall.
Building Solutions,
Timber floor finishes should be applied in accordance with
2 Heathrow Boulevard,
the recommendations of BS 8201. Chipboard should be to
284 Bath Road, West Drayton, Middlesex, UB7 0DQ.
BS 5669 Type C4 18mm thick laid with staggered cross
Tel: 020 8917 5050 - Fax: 020 8917 5413
joints. All joints should be bonded with wood grade PVA
adhesive to avoid their squeaking in use; check the
FLOORMATE 200-X; STYROFOAM SP-X;
compatibility of the adhesive with FLOORMATE insulation
FLOORMATE 500-X; FLOORMATE 700-A
prior to laying. Wedge the panels temporarily at the
Board sizes: 1250 x 600mm and 2500 x 600mm†
perimeter until the adhesive has set.
Edge profile: butt edge, ship lap
Allow a gap of 10mm or 2mm per linear metre of flooring
Compressive strength†: 200kN/m2, 350kN/m2,
(whichever is the greater) between the chipboard and the
500kN/m2, 700kN/m2
perimeter wall. Proprietary expansion joints may be
Design loading† : 60kN/m2, 110kN/m2, 150kN/m2,
required for uninterrupted floor runs greater than 5 metres,
250kN/m2
the joints should allow for 2mm expansion per metre of
Fire classification: Reaction to fire: BS EN 13164 -
floor.
Euro class E
Where there is a likelihood of regular water spillage (e.g.
bathrooms and kitchens) the chipboard must be protected
by a waterproof covering such as continuous sheet vinyl
turned up at abutments.
For details of laying other timber overlays refer to BS 8203.
›››
lay sheets on a level bed of sand, not less than 13mm
thick.
›››
seal all joints by overlaying with 500 gauge
polyethylene with lapped joints.
›››
ensure that insulation is covered with concrete
blinding (see section E10) before fixing slab
reinforcement.
† select appropriate values using STYROFOAM Solutions
Product Data - See page 09
42
Insulating groundbearing floors: design
M10 Cement:sand/concrete screeds/toppings
K11 Rigid sheet flooring ...
290 Floating construction
›››
›››
›››
Insulation: (as E20)
Thickness: (as E20)
Manufacturer and reference: (as E20)
FLOORMATE 200-X; STYROFOAM SP-X;
FLOORMATE 500-X; FLOORMATE 700-A
225 Particleboard floating floor
›››
›››
›››
›››
›››
Base: ...
Preparation: ...
Insulation: (as E20)
Thickness: (as E20)
Manufacturer and reference: (as E20)
Board size: (as E20)
FLOORMATE 200-X; STYROFOAM SP-X;
Edge profile: (as E20)
FLOORMATE 500-X; FLOORMATE 700-A
Compressive strength: (as E20)
Board size: (as E20)
Design loading: (as E20)
Edge profile: (as E20)
Fire classification: (as E20)
Compressive strength: (as E20)
Design loading: (as E20)
›››
all abutments with walls, columns etc. for full depth of
screed.
›››
Fire classification: (as E20)
lay insulation with tight butt joints and continue up at
lay separating layer of 500 gauge polyethylene sheet,
lapping 100mm at joints.
›››
›››
Vapour control layer: ...
Flooring: particleboard to BS EN 312, Type P5
Thickness: ...mm
Edges: tongued and grooved all edges
Insulation below screed may also be specified with clause
Fit boards together tightly with end joints staggered.
M13 - 260.
Glue all joints.
Insulation below flooring may also be specified with:
K11 - 115/125/135/145/215/235/245,
K20 - 150/160, K21 - 120/130
STYROFOAM Solutions
43
Insulating groundbearing floors: installation
Installation sequence FLOORMATE under
screed (figure 41)
1.
When the concrete slab is sufficiently cured check the
surface for trueness and, if necessary blind with sand.
2.
Lay FLOORMATE boards with edges tightly butted.
3.
Overlay with a slip sheet with edges lapped.
4.
Lay screed and leave to cure for at least seven days.
Installation sequence FLOORMATE below
timber (figure 42)
Figure 40 >> Floormate under slab
1.
Lay DPM over the concrete slab.
2.
Lay FLOORMATE board with edges tightly butted.
3.
Overlay FLOORMATE with slipsheet with joints lapped
and edges turned up.
4.
Fit flooring boards, leaving a 10mm gap at perimeters.
Key points
›››
avoid point loading (eg wheelbarrows and foot traffic)
of FLOORMATE thermal insulation during installation;
provide scaffold boards or similar.
›››
protect FLOORMATE boards and DPM while concreting
or screeding.
Figure 41 >> Floormate under screed
›››
›››
lay insulation over whole floor leaving no gaps.
stagger board joints when laying insulation in two or
more layers.
›››
use temporary timber battens over perimeter walls to
protect edge insulation (if present).
›››
tape joints in DPM and lap with wall DPC. Ensure DPM
is correctly positioned and continuous with DPC.
›››
ensure all damp proof membranes and slip sheets are
installed and turned up correctly.
›››
ensure reinforcement and installation procedures for
screeds are carried out in accordance with the
specification.
Figure 42 >> Floormate below timber
›››
applied.
Installation sequence FLOORMATE under slab
(figure 40)
1.
Compact fill and blind with sand.
2.
Fit 25mm thick FLOORMATE boards vertically at the
›››
Lay FLOORMATE boards with edges tightly butted.
4.
Overlay with the DPM, lapping and sealing joints. Turn
up at edges ready to link into the DPC.
5.
Lay the floor slab.
at penetrations of the floor slab by service and soil
pipes, take care to avoid ground moisture bypassing
the DPM. Cut FLOORMATE boards to fit the
penetration closely. Fill small gaps with an expanding
edges.
3.
allow screeds to cure before any floor finishes are
polyurethane foam to form an airtight seal.
›››
where services are run within a concrete slab, they
should be tested before the slab is laid.
›››
keep service runs beneath the flooring to a minimum,
ensure they are accessible for maintenance. Allow a
44
gap of at least 10mm between timber based flooring
panels and the wall.
Insulating suspended floors: design
General considerations
Suspended floors are supported on the walls and can be
formed from:
›››
›››
›››
›››
➀
➄
➁
timber joists and boarding.
➂
cast in-situ concrete.
concrete beams and block infills.
precast concrete units.
Intermediate floors are by definition suspended and are
➃
only required to incorporate thermal insulation if the floor
divides a heated space from an unheated space or outside
air, or when a floor slab extends to form a balcony over the
outside air.
FLOORMATE insulation is designed to give the maximum
benefit in suspended ground and intermediate floors:
›››
➀ FLOORMATE
➁ DPM
➂ concrete slab
➃ hardcore with sand
blinding
➄ DPC
Figure 43 >> FLOORMATE boards over cast in-situ concrete
a range of compressive strengths to match loading
conditions.
›››
›››
➀
➁
➂
resistant to ground moisture.
thicknesses from 25mm to 100mm allow thermal
performance to be matched to project requirements.
➃
Consult the technical data on Page 09 for the full physical
and performance properties of FLOORMATE.
Suspended ground floors of cast in-situ
concrete
Ground floor slabs may be formed in-situ onto fill which is
➀ board or screed finish
➁ VCL/SS
➃ beam and block floor
with levelling topping
➂ FLOORMATE
Figure 44 >> FLOORMATE boards over beam and block floor
expected to settle and is therefore regarded merely as
temporary shuttering. In such cases the slab must be
➀
➁
➂
designed and reinforced as a suspended slab even though
it is, initially, ground-bearing (figure 43). In this type of floor,
the DPM should be laid directly on the slab and then
➃
covered by the FLOORMATE, followed by the other layers of
the floor construction.
Beam and block and precast ground floors
Beam and block floors (figure 44) and precast floors (figure
45) should be levelled ie. no more than 5mm deviation
➀ board or screed finish
➁ VCL/SS
➂ FLOORMATE
➃ precast floor with
levelling topping
Figure 45 >> FLOORMATE boards over precast concrete floor
under a 3m straight edge with a screed or grouted prior to
laying FLOORMATE boards. FLOORMATE insulation is best
applied over the beams and beneath a screed or boarded
finish.
STYROFOAM Solutions
45
Insulating suspended floors: design
Suspended ground floors of timber
Thermal bridging
Timber joisted floors involve no wet trades, are simple to
In suspended ground floors, as with groundbearing floors,
install and avoid the need for large amounts of compacted
it is important to detail wall/floor junctions to avoid
backfill. They can be insulated using FLOORMATE extruded
thermal bridges.
polystyrene in several ways:
›››
›››
›››
In exposed floors, there is a risk of thermal bridging at the
between joists (figure 46).
wall/floor junction where the wall is built off a projecting
attached to bottom of joists.
floor. Ensure continuity of wall and floor insulation (figure
on decking (for example suitable grade of chipboard)
47) or use insulating blockwork and overlapping layers of
laid over joists.
insulation (figure 48) or insulate internally (figure 49).
FLOORMATE boards should not be positioned directly
onto the joists.
Where the floor structure is timber joists, ensure the space
between the joist and the wall is packed with thermal
insulation or fix FLOORMATE boards to the underside of the
floor externally and apply a vandal proof soffit. Refer also to
BRE BR 262 ‘Thermal insulation: avoiding risks’ and
➀
DEFRA/DTLR ‘Robust Details’.
➁
The detailing of balconies requires careful attention to
➂
avoid problems with thermal bridging; for guidance refer to
BRE BR 262.
Figure 46 >> FLOORMATE boards between joists
➀
➁
➂
➀ WALLMATE CW-X
➁ projecting floor
➂ FLOORMATE
Figure 47 >> Exposed wall/floor junction, outer leaf supported
independently
46
Insulating suspended floors: design
Cables run close to FLOORMATE insulation may need to be
de-rated in line with IEE Regulations. PVC-covered cables
likely to come into contact with FLOORMATE insulation
should be protected by metal or uPVC conduit or trunking
➀
➁
➂
to avoid the risk of plasticiser migration from the PVC.
Specification
The following NBS clauses are relevant to the specification
of FLOORMATE insulation:
P10 Sundry insulation
255 Rigid board insulation supported between
➃
floor joists
➀ VCL/SS
➁ FLOORMATE
›››
›››
➂ WALLMATE CW-X
➃ DPC/tray
Insulation: extruded polystyrene boards
Thickness:
25/30/35/40/50/60/70/80/90/100/120/140† mm
†delete
Figure 48 >> Exposed wall/floor junction, insulation applied
internally
›››
as appropriate
Manufacturer and reference:
Dow Chemical Co. Ltd,
➀
Building Solutions,
2 Heathrow Boulevard,
284 Bath Road, West Drayton, Middlesex, UB7 0DQ.
Tel: 020 8917 5050 - Fax: 020 8917 5413
➁
➂
FLOORMATE 200-X
Board size: 2500mm x 600mm
Edge profile: butt edge
Compressive strength: 200kN/m2
Design loading: 60kN/m2
➃
Fire classification:
Reaction to fire: BS EN 13164 - Euroclass E
➀ STYROFOAM LB - X
/plasterboard laminate
➁ VCL/SS
➂ FLOORMATE
➃ DPC/tray
Figure 49 >> Exposed wall/floor junction, lightweight blockwork
inner leaf
›››
Supports: saddle clips†† / nails†† / preservative treated
battens††
›››
Fit tightly with closely butted joints, leaving no gaps
Services
Central heating pipes are often run in the void below
suspended timber floors or within the joist depth.
When FLOORMATE boards are incorporated in the
† select appropriate values using STYROFOAM Solutions
Product Data
†† delete as appropriate
construction, it is best to locate the pipework above the
insulation to minimise heat loss into the cold void (figure
Insulation laid on boarding may also be specified with:
50). The pipes should be insulated to concentrate heat
K11 - 115/125/135/145/215/235/245, K20 - 150/160,
output at the radiators.
K21 - 120/130
Run gas pipes below the FLOORMATE boards.
STYROFOAM Solutions
47
Insulating suspended floors: installation
Installation sequence
Beam and block and precast floors
(figures 45 and 45)
1.
Lay topping to provide necessary level surface.
2.
Lay FLOORMATE boards with edges tightly butted.
3.
Overlay with slip sheet with edges lapped.
4.
Lay board or screed finish (allow to cure for at least
7 days).
Timber floors (figure 51)
1.
Fix preservative treated battens to the sides of floor
joists so the height of the joist above the batten is the
same as the thickness of the FLOORMATE boards.
2.
Cut FLOORMATE boards so they will fit tightly between
the joist and lay on the battens.
Figure 50 >> Services above FLOORMATE boards
3.
Lay and fix floor boards.
Key points
Beam and block and precast floors
›››
refer to Key Points under Insulating groundbearing
floors: installation.
Timber floors
›››
fit FLOORMATE boards tight to the underside of the
floor to avoid air movement between the FLOORMATE
boards and the floor.
›››
pack FLOORMATE insulation into any spaces at the
perimeter.
›››
at penetrations cut boards around the pipe or duct
and seal the gap with polyurethane foam.
Figure 51 >> FLOORMATE boards between joists
›››
ensure underfloor ventilation is clear and not
restricted at sleeper walls.
48
Insulating floors: renovating floors
General considerations
Improving the thermal performance of existing floors
Renovating with a concrete groundbearing
floor
during renovation can be desirable and economic.
When replacing an existing timber floor with a concrete
Existing timber ground floors may be overlaid with
groundbearing floor follow the guidance on pages
insulation and a new flooring surface.
35 - 44 of this brochure, taking account of the following:
Timber ground floors in pre-war properties often suffer
›››
non-settling fill to a maximum depth of 600mm.
from rot and insect infestation while the underfloor void
can be a habitat for rodents. Such floors may be replaced
fill deep sub-floor voids with hard core or a suitable
›››
if the DPM cannot be tied into the DPC, it should be
dressed up behind a skirting.
by a groundbearing concrete floor incorporating thermal
insulation (see figure 52).
›››
Overlaying existing timber floors
FLOORMATE extruded polystyrene can also be used to
When upgrading an existing timber floor the skirting
provide floor insulation in conversions, for example when
should be removed and the appropriate grade of
converting an agricultural building to domestic use.
FLOORMATE laid. The flooring and finish is then laid on it.
Old concrete, stone or earth floors should be removed
The skirting will then be reinstalled or replaced and doors
down to a level suitable to accept the new insulated floor.
shortened to open over the new level.
Site assessment and preparation in refurbishment projects
block off ventilation openings.
should follow the same procedures as for new-build.
➀ timber floor finish
➀
➁
➂
➃
➆
➁ VCL/SS
➂ joist
➃ concrete slab
➄
➅
➄ DPM
➅ FLOORMATE
➆ DPC
Figure 52 >> Replacement of decaying timber floor with a new insulated concrete floor
STYROFOAM Solutions
49
Insulating structure below ground
General considerations
PERIMATE DI-A is designed to give the maximum benefit
Structure below ground must prevent ground water
when insulating structures below ground:
reaching the interior of a building in order to maintain
›››
›››
suitable internal conditions (see BS 8102 for gradings).
A common way of providing waterproofing is to use
externally applied tanking membranes of mastic asphalt or
bituminous sheet. In such constructions insulation can be
shiplapped edges ensure continuity of insulation.
vertical channels cut in the face of the board drain
water away.
›››
a thin layer of filter fabric bonded to the surface
prevents soil particles blocking the channels.
located outside the waterproofing, where it will:
›››
›››
insulate the structure.
Consult pages 5 and 9 for the full physical and
protect the tanking material from physical damage
performance properties of PERIMATE DI-A.
caused by the rest of the construction process or by
›››
the backfill material.
Drainage
drain water away from the structure, reducing the
Water collecting at the base of the PERIMATE DI-A boards
hydrostatic pressure on the tanking membrane.
must be drained away by filter drains formed with
perforated or porous pipes laid above the footings or
When externally insulating basement walls the insulation
boards are laid against the tanking membrane and the
excavation is then backfilled (figure 55). The construction is
suitable for new build; it is also suitable for refurbishment
collector drains formed from perforated pipes laid in
granular material (figure 54). Depending upon ground
conditions drains may be connected to surface drainage
systems or soakaways.
projects. For guidance on constructing basements consult
the Approved Document: Basements for dwellings.
Thermal performance
The STYROFOAM Solution for externally insulating
Methods for calculating U-values for basements are given
basement walls is PERIMATE DI-A.
in BS EN 13370 and the Approved Document ‘Basements
for dwellings’. For assistance with U-value calculations
contact Dow.
Observe the following installation guidance to gain the
maximum benefit from PERIMATE DI-A insulation.
➀
➁
➂
➃
➄
➀ structure below
ground
➂ PERIMATE DI-A
➁ tanking membrane
➄ ground
➃ backfill
Figure 53 >> Principles of insulating structure below ground
50
Insulating structure below ground: installation
Installation sequence
➀
1.
manufacturer's instructions.
➁
➂
➃
2.
Lay the drainage system.
3.
Install PERIMATE DI-A insulation against the tanking
membrane, with the grooved face outward, using a
➄
suitable adhesive such as Insta-Stik™.
➅
4.
➆
➇
Install the tanking membrane according to
Backfill to the designated level.
Key points
›››
›››
ensure boards butt together tightly.
when installing more than one row of boards ensure
the filter fabric on upper rows laps over that of lower
➀ structure below
ground
➄ ground
➁ tanking membrane
➆ perforated pipe
➂ PERIMATE DI-A
➃ backfill
rows.
➅ geo-textile
➇ granular material
Figure 54 >> Drainage by collector drain
™ Tradename of Dow Chemical Company
STYROFOAM Solutions
51
Insulating walls: design
Problems with cavity walls
Externally insulated solid walls
The conventional cavity wall construction was intended
Solid masonry walls may be insulated on their external
originally to prevent problems of damp penetration of thin
surface and the insulation covered by an external finish
brick walls. It has since been adapted to meet successive
such as render, boarding or tiling (see figure 56). That
changes in Building Regulations, most notably with the
construction offers numerous benefits:
introduction of thermal insulation into the cavity
›››
all the thermal mass of the wall lies within the
(see figure 55).
insulation envelope, resulting in a structure with a
With the latest changes in Part L it has become apparent
slow thermal response which is well suited to
that cavity wall construction may not be a practicable
continuously heated buildings;
method of achieving the necessary standards of thermal
›››
moisture, which eliminates one route for air infiltration,
performance:
›››
ties to achieve structural stability;
›››
wider cavities may not comply with the requirements
for robust details to Part E;
›››
making it easier to construct buildings with low rates
the thickness of thermal insulation requires wider
cavities which, in turn, require longer and more wall
solid walls do not require vented cavities to drain away
of air permeability;
›››
detailing of windows and doors is easier as there is
only one structural plane to consider within the wall;
›››
large format blocks and thin joint systems speed
construction and reduce the effect of thermal bridging.
thicker walls will either reduce the available space
within the building or increase the building footprint,
which may, for example, lower the density of
dwellings in a development;
›››
vents to the cavity results in high levels of air infiltration.
To avoid those and other problems designers should
consider other forms of wall construction.
Figure 55 >> Conventional cavity wall construction
Figure 56 >> Externally insulated solid walls
52
Insulating walls:
Internally insulated walls
Walls may be insulated on their internal face, with the
insulation applied between the structure and the internal
finish (see figure 57). Installing the insulation in that way
will mean the thermal mass of the wall is outside the
insulation, resulting in a rapid thermal response, suitable for
buildings which are intermittently heated.
Internally insulating walls is a useful solution for upgrading
the thermal performance of walls in the course of projects
which require consequential improvements. It will not
affect the external appearance of the building.
Timber or steel framed walls
Figure 57 >> Internally insulated walls
In framed wall constructions of timber or steel the
insulation is fitted between the studs, combining the
structure and thermal insulation into the same plane. The
internal face of the wall is lined with plasterboard, whilst
the external face can be finished with a single leaf of brick,
tile hanging, boarding or a render system (see figure 58).
Where necessary the thermal performance of the wall can
be improved by installing a further layer of insulation across
the face of the studs: that will also reduce the effects of
thermal bridging.
The use of framed wall construction has become increasingly
common, most notably in the Republic of Ireland and
Scotland where the required U-values for walls are already
Figure 58 >> Timber or steel framed walls
as low as 0.27W/m2K and 0.30W/m2K respectively.
STYROFOAM Solutions
Partial fill cavity
U value
0.25
0.28
0.30
0.35
Block λ (W/mK)
The STYROFOAM solution for partial fill cavity wall
Dense
1.63
100
90
80
70
Medium
0.51
100
90
80
70
WALLMATE CW-X is designed to give the maximum benefit
Lightweight
0.19
90
80
70
60
in wall construction:
Solid - internal insulation
110
90
80
70
›››
Timber frame - insulation between and external to studding
constructions is WALLMATE CW-X.
tongue and grooved edges ensure a good interlock
between boards, avoiding thermal bridging,
›››
›››
Stud depth
90mm
the strong, rigid boards are self-supporting,
low water absorption means performance is
unaffected by moisture.
140mm
90+30
90+25
90+25
90
140+25
140
140
140
15% timber fraction
Table 16 STYROFOAM thickness (mm) to ahieve U-values (W/m2.K)
For the full physical properties and performance
characteristics of WALLMATE CW-X see Product Data.
Other STYROFOAM products can be used for internally
insulated solid walls and timber or steel frame walls.
STYROFOAM Solutions
53
Insulating single-ply roofs
The use of single-ply waterproofing membranes in
ROOFMATE RL-X is designed to give the maximum benefit
combination with metal deck systems enables the construction
in single-ply roof construction:
of lightweight, long-span roofs at pitches of 10˚ and below.
›››
Siting rigid insulation above the decking brings the whole
roof structure, with the exception of the waterproofing
high compressive strength helps reduces the risk of
mechanical fixings working loose after installation.
›››
enhanced dimensional stability minimises the number
membrane, within the insulating envelope, which:
of fixings required and reduces board movement in
›››
›››
›››
service.
maintains the structure at an even temperature.
reduces the risk of harmful condensation.
minimises thermal movement within the structure.
Single-ply metal deck roofs offer a cost effective way of
covering large spans. Installation of the roof covering can
begin as soon as the structural steelwork is in place,
allowing the construction of the roof to take place
independently of many other parts of the project.
›››
›››
supports pedestrian traffic during installation.
minimal water pick-up enables insulation to be laid in
any weather.
›››
›››
easy to install.
ROOFMATE RL-X is suitable for use under all single-ply
polymeric waterproofing membranes.
Consult Page 08 for the full physical and performance data
of ROOFMATE RL-X.
General considerations
Lightweight single-ply roofs usually consist of profiled steel
Choice of membrane
decking fixed to steel purlins and overlaid with a vapour
ROOFMATE RL-X insulation is designed for use under light
control layer. Rigid insulation board is fixed through the
coloured (grey through white) single-ply polymeric
crowns of the decking and then overlaid with a light
membranes. ROOFMATE RL-X insulation is not suitable
coloured, single-ply, polymeric waterproofing membrane
for use under dark coloured waterproof coverings such
which is usually mechanically fixed through the decking
as bituminous felt or black EPDM. To prevent plasticiser
(see figure 59).
migration PVC membranes should be isolated from
ROOFMATE RL-X boards by a suitable separating layer.
The STYROFOAM Solution for insulating single-ply
roofs is ROOFMATE RL-X.
Loading
The roof structure must be strong enough to withstand the
maximum predicted loads with a suitable factor of safety.
ROOFMATE RL-X boards are suitable for occasional
pedestrian maintenance traffic but if more frequent traffic
is expected, additional protection of the membrane and
boards is required, eg. walkway layers or concrete paving
slabs on spacers.
U value
0.16
0.18
0.20
0.25
0.35
ROOFMATE RL-X
200
180
160
120
80
Table 17
Figure 59 >> Mechanically fixed single-ply membrane
54
ROOFMATE RL-X thickness (mm) to achieve U-values (W/m2.K)
Insulating single-ply roofs
Securement
Consult a fire Safety Engineer where any doubt exists on
Fixings for the roof covering and insulation must able to
the need for fire protection.
withstand predicted wind-uplift forces; refer to the
Thermal performance
membrane supplier’s and fixing manufacturer’s data for
loading limits and calculation methods.
Table 17 shows the amount of ROOFMATE RL-X required to
meet a range of U-values.
Each ROOFMATE RL-X board should be secured to the deck
with three fixings, each having a washer of at least 20cm2
Condensation
area: these are in addition to any used to secure the
Condensation can cause rot, decay and the corrosion of
waterproof membrane to the deck. Half boards or less may
metal components, leading to roofing failure. Whilst the risk
be secured with two fixings.
of condensation is low for a metal deck roof featuring
ROOFMATE RL-X insulation under normal environmental
Drainage
conditions, condensation risk analysis should still be
Good drainage is vital to the long term performance of a
performed, using the method given in BS EN 150 13788.
flat roof. To ensure the minimum finished falls of 1:80
recommended in BS 6229 falls should be designed at 1:40.
If the calculation predicts harmful levels the design should
be reassessed. Consider:
Falls can be constructed by
›››
›››
›››
designing the roof structure to falls.
›››
›››
reducing the humidity level within the building.
increasing the thickness of thermal insulation.
applying a screed to falls or
adding tapered insulation.*
Specification
Use the following NBS clause to specify ROOFMATE RL-X
When assessing the requirements of gutters and outlets
insulation in a single-ply roof:
designers should refer to BS EN 12056-3.
J42 Single layer polymeric roof covering
Fire
Building Regulation B4 requires roofs to resist the spread of
fire over the roof and from one building to another. Roof
452 Warm deck insulation
›››
›››
Insulation: extruded polystyrene board to BS EN 13164
Manufacturer and reference:
covering classified according to BS 476: Part 3: 1958 as AA,
Dow Chemical Co. Ltd,
AB or AC may be used without restrictions (see Approved
Building Solutions,
Document B, Technical Standard D in Scotland).
2 Heathrow Boulevard,
Experience suggests a roof construction which has a
284 Bath Road, West Drayton, Middlesex, UB7 0DQ.
protective layer of 50mm of gravel above the
Tel: 020 8917 5050 - Fax: 020 8917 5413
waterproofing layer will achieve an AA rating. Nonballasted, mechanically fixed, plasticised PVC roofing
ROOFMATE RL-X
membranes will normally achieve an AB rating.
Thickness: 50/60/80/120 mm
BRE document ‘Thermal insulation: avoiding risks’ indicates
Board size: 2500mm x 600mm
cellular plastic insulants laid directly on a metal deck may
Edge profile: tongue and groove
melt when there is a fire source within the building.
Compressive strength: 300 kN/m2
Improved fire protection may be provided by the use of:
Design loading: 110 kN/m2
›››
›››
›››
sprinkler systems.
Fire classification: EUROCLASS E
fire rated suspended ceilings.
fire barriers which form a break in the insulation layer,
giving effective fire separation.
*
A tapered insulation system based on STYROFOAM is available from the
A. Proctor Group who offer a full design and installation service for cut-to-falls
insulation.
STYROFOAM Solutions
55
Insulating pitched roofs
Inroduction
Pitched roofs can be insulated at ceiling level or at rafter
line: applying insulation at rafter line brings all the building
volume within the insulation envelope (figure 60).
By insulating at rafter line:
›››
the insulated space enclosed by the building
STYROFOAM Solution
The STYROFOAM solution for insulating pitched roofs at
rafter line is ROOFMATE RL-X, a tongue and grooved
STYROFOAM board (figure 61).
Agrément Certificate 87/1836 covers the use of
ROOFMATE RL-X in warm pitched roof construction.
envelope is substantially increased without altering
the structural design; the additional space can be used
as part of the initial design or converted for use at a
later date.
›››
the whole of the building fabric is kept at a similar
temperature, thereby reducing the risk of
condensation on structural members.
›››
thermally induced movement is reduced because the
roof structure is not subject to extremes of
temperature.
›››
a board-insulated roof offers greatly improved
resistance to wind-driven rain and fine snow.
›››
pipes, tanks and services in the loft space are
protected from freezing temperatures.
›››
pipes and wiring at ceiling level are not hidden by
insulation.
Insulating warm roofs
Warm roofs may be formed with the insulation installed
part above and part between the rafters (figure 60).
Warm pitched roof constructions are not covered by any
British Standard, although some guidance is contained in
BS 5250, BS 5534 and BRE document ’Thermal insulation:
avoiding risks’.
Figure 60 >> Insulating above and between the rafter with
ROOFMATE RL-X
56
Figure 61
Insulating pitched roofs
Fixing ROOFMATE RL-X boards
ROOFMATE RL-X boards installed over the rafter are secured
by the fixings used to secure the counterbattens, which pass
through the insulation and into the rafters. The
counterbattens, which will normally be 32 or 50mm thick,
support the tiling battens (figure 61).
The counterbattens are secured using specialised fasteners,
Underlays
Roofing underlays form a second line of defence against
wind-driven rain and snow. Underlays used in warm
pitched roof constructions should:
›››
›››
›››
have very low resistance to the passage of water vapour.
be compatible with the insulation.
not “tent” when laid in contact with the insulation.
e.g. Helifix Inskew, Proctor PR nail, Ancon Staifix - Thor
For this application Dow recommend water vapour
Helical Batten fixings. The type and number of fasteners
permeable underlays with a water vapour resistance less
should be calculated using the methods in BS 5534: Part 1
than 0.25MNs/g (such as ROOFSHIELD†, TYVEK†† or
and fasteners manufacturer's data.
PERMO†††) certified by Agrément.
The tiling battens can be secured directly to the
The underlay may be laid either directly on the ROOFMATE
counterbattens using normal fasteners.
RL-X boards or over the counter battens (figure 63). A rigid
Joints between adjacent boards of ROOFMATE RL-X do not
require cross noggins: the tongued and grooved edges of
carrier may be required to prevent ponding at the eaves
(figure 64).
ROOFMATE RL-X are self-supporting and ensure continuity
of insulation at all joints.
However, the boards must never be stood on or used
as a working platform.
The ROOFMATE RL-X boards should be laid with their
length parallel to the ridge/eaves with the tongue facing
up the roof slope (figure 62).
ROOFMATE RL-X boards cut-to-size can be installed
between the rafters and secured in place by support
underlay laid directly
on ROOFMATE-RL-X
underlay draped over
the counter battens
Figure 63
battens
board width / length
up slope
Figure 62 >> Joints in ROOFMATE RL-X
†
A trade name of Don & Low Nonwovens
††
A trade name of Du Pont
†††
A trade name of Klober Limited
Figure 64
STYROFOAM Solutions
57
Insulating pitched roofs
Thermal performance
Ventilation
Table 12 below shows the amount of ROOFMATE RL-X
required to achieve a range of U-values..
does not require provision for ventilation to remove
Table 18 ROOFMATE RL-X thickness (mm) to achieve U-values (W/m2.K)
0.14
0.16
Above rafter
0.18
The loft space enclosed within a warm roof construction
0.20
0.25
condensation. If the loft is to be used as habitable space, it
will need to comply with the requirements of Building
Regulation F1 (Regulation 23 in Scotland).
Between rafter
60mm
180
140
120
100
60
80mm
160
120
100
60
50
Moisture build up in the space between the outer roof
covering and the water vapour permeable underlay must
8.3% timber fraction 50mm rafters at 600mm spacing
be prevented by venting moist air to atmosphere. The
Continuity of thermal insulation
surface irregularities of natural slates and cambered plain
Thermal insulation of the roof should be continuous, with
tiles will usually provide sufficient air paths. However, close-
gable ends being insulated to their full height.
fitting coverings, such as those formed with tightly
Thermal bridging can occur where boards are cut to fit as
interlocking tiles, synthetic resin slates or profiled metal
at junctions, ridges, abutments and penetrations. Fill all
sheets, will require specific provision for air movement in
gaps with sprayed polyurethane foam or flexible foam strip
the form of vents, especially if the roof pitch is low or the
to avoid air leakage which may lead to localised
roof slopes are large or of complex shape.
condensation.
Ventilation is not however required between the underlay
Please refer to DEFRA/DTLR ‘Robust Details’ and BR 262
and insulation.
‘Thermal Insulation - avoiding risks’
Fire
Condensation
The use of ROOFMATE RL-X insulation boards will not affect
Adopting a warm roof construction moves the condensation
the fire rating of tiled roofs when evaluated by assessment
plane to the batten space where any condensation which
or when tested to BS 476: Part 3: 1958. To comply with
occurs can be dispersed by natural air movement.
Building Regulation B2 (Regulation 12 in Scotland) for
The closed cell structure of ROOFMATE RL-X insulation
internal fire spread ROOFMATE RL-X boards must be
makes it resistant to the passage of water vapour: calculation
protected by a lining, such as plasterboard.
will often show no need for a vapour control layer.
For further information on the fire performance of
It is however advisable to install a vapour control layer
ROOFMATE RL-X boards see BS 6203 and Agrément
ensuring that it is as convection tight as possible. Where
Certificate 87/1836.
the building is likely to have a high level of humidity, as in
the case of swimming pools or commercial kitchens,
condensation risk assessment should be undertaken by a
suitably qualified professional. A method for calculating the
risk of interstitial condensation is given in BS EN ISO 13788.
58
Insulating pitched roofs
Installation sequence
1.
7.
Fix a 60mm thick timber stop batten across the rafters at
eaves (A).
2.
Fit ROOFMATE RL-X boards cut-to-size between the rafters
from within the loft space. Press tight against the
ROOFMATE RL-X boards and fix by nailing support battens
Lay ROOFMATE RL-X boards with long edges at right
to the rafters (F).
angles to the rafters and with the tongue pointing up the
slope (B).
3.
Butt the first row of boards tight against the stop batten.
Continue laying up the slope towards the ridge.
At ridge butt ROOFMATE RL-X to the ridge board (B) or to
ROOFMATE RL-X on the opposite slope. (C).
4.
Fix ROOFMATE RL-X boards temporarily by occasional
nailing until permanently secured by the counter battens.
5.
Key points
››› Ensure ROOFMATE RL-X boards interlock tightly.
››› Cut and fit boards neatly.
››› Seal any gaps, particularly at cut joints.
››› Do not stand on ROOFMATE RL-X or use as a working
platform.
At all cut edges, junctions and penetrations trim
ROOFMATE RL-X boards neatly to fit (D) (E). Seal any
gaps with polyurethane foam.
6.
either: (a) lay the underlay directly onto the ROOFMATE
RL-X boards and secure with counter battens; or (b)
secure the ROOFMATE RL-X boards with counter battens,
then drape the underlay over the counter battens and
secure with tiling/slating battens.
(Refer to underlay supplier’s instructions).
A
B
C
E
D
E
STYROFOAM Solutions
59
Insulating agricultural buildings
Modern farming methods require efficient buildings in
Thermal performance
which temperature and humidity can be closely controlled.
Building Regulations do not impose any requirement for
Effective insulation is vital for the design and construction
the thermal performance of agricultural buildings. Table 19
of buildings which will:
shows the recommended U-values for walls and roofs of
›››
›››
›››
agricultural buildings given in BS 5502.
provide economic crop storage.
extend the effective period for crop storage.
provide the optimum environment for healthy growth
of livestock.
›››
reduce the risk of livestock suffering thermal stress by
minimising summer heat gains and winter heat loss.
Condensation
The high humidity levels required in crop stores to minimise
water losses from crops held in storage and the warmth
and moisture given off by livestock present considerable
condensation risks within agricultural buildings.
Insulation in agricultural buildings must be able to
withstand:
›››
›››
›››
Condensation on inside surfaces, which could damage
stored crops can be prevented by insulating inside the
structural framework. However, insulation applied to the
high humidity.
impact damage.
regular cleaning, including pressure hosing.
outside of the structural framework will prevent surface
condensation and prevent interstitial condensation by
maintaining the framework at the same temperature as the
interior of the building.
Guidance on the use of insulation in agricultural buildings
can be found in BS 5502.
The STYROFOAM Solution for insulating agricultural
buildings is ROOFMATE RL-X.
Fire
Agricultural buildings used principally for retailing, packing
or exhibiting are required by Building Regulations to have a
fire resistant lining: 13mm plasterboard applied over
ROOFMATE RL-X is designed to give the maximum benefit
STYROFOAM insulation will meet that requirement. All
in agricultural buildings:-
other agricultural buildings are excluded from the scope of
›››
›››
›››
unaffected by moisture.
Building Regulations. BS 5502: Part 23 gives recommendations
sufficiently rigid to span purlins unsupported.
for fire performance of building elements.
withstands pressure hosing or steam cleaning.
Roofs
(W/m2K)
Walls
(W/m2K)
Heated piggeries 1
0.5
0.5
Unheated piggeries 1
0.6
0.6
Poultry houses 2
0.4
0.4
Crop storage 3
0.4-0.45
0.5
Table 19 Recomended U-values for agricultural buildings
1) BS 5502: Part 42
2) MAFF booklet ‘Heat Stress in Poultry - solving the problem’
3) BS 5502: Part 71
60
Insulating agricultural buildings
General
ROOFMATE RL-X
The walls of agricultural buildings may be insulated on the
Thickness: 30/40/50/60/80*mm
inside or outside of the loadbearing structure, whilst roofs
*delete as appropriate
may be insulated above purlins or with the insulation
Board size: 2400 x 600mm
forming a horizontal ceiling.
Edge profile: tongue and groove
Compressive strength: 250kN/m2
Roofs
Fire classification:
Applying ROOFMATE RL-X insulation in the plane of the
BS 3837: Part 2: 1990: Appendix C
roof enables maximum use to be made of the space
Operating temperature: -50°C to +75°C
enclosed by the structure. Ventilation will be required
between the roof covering and the insulation to prevent
the build up of condensation. Where ventilation systems
require flat ceilings uninterrupted by structural members
the insulation boards should be installed to the underside
of the joists.
ROOFMATE RL-X insulation should be fixed as follows:
›››
Above the purlins: ROOFMATE RL-X boards will be
secured by the fixings for the cladding (figure 64).
›››
Below the purlins/horizontal ceiling: for timber frames
ROOFMATE RL-X boards should be nailed directly to
Figure >> 65 Insulation above purlins
the timber using flat headed galvanised or aluminium
alloy nails (figure 65). For steel or concrete frames,
battens should be fixed to the frame (by shot-firing to
steel or strapping to concrete) and the ROOFMATE RL-X
boards nailed directly to the battens (figure 66).
Specification
Agricultural buildings are not specifically treated in NBS.
The following text can be used to specify ROOFMATE RL-X
insulation.
›››
›››
Material: Extruded polystyrene board
Manufacturer and reference:
Figure >> 66 Insulation below purlins
Dow Chemical Co. Ltd.
Building Solutions,
2 Heathrow Boulevard,
284 Bath Road, West Drayton, Middlesex UB7 0DQ.
Tel 020 8917 5049
Fax 020 8917 5413
Figure >> 67 Insulation at ceiling line
STYROFOAM Solutions
61
References
Agrément certificates
›››
›››
›››
›››
88/2105 Cavity walls
97/3431 Inverted roofs
Approved Documents to the Building Regulations
›››
– C Site preparation and resistance to moisture
›››
dwellings
›››
Part 1: 1996: Design.
›››
slabs with profiled steel sheeting.
›››
BS 5268: Structural use of timber.
Part 4: Fire resistance of timber structures.
– Section 4.2: 1990: Recommendations for calculating
fire resistance of timber stud walls and joisted floor
– L2A Conservation of fuel and power in new
constructions.
buildings other than dwellings
Part 7: Recommendations for the calculation basis for
– L2B Conservation of fuel and power in existing
span tables.
buildings other than dwellings
Regulations
BS 5950: Structural use of steelwork in building.
Part 4: 1994 Code of practice for design of composite
dwellings
Technical Handbooks to Building Standards Scotland
BS 5427: Code of practice for the use of profiled sheet
for roof and wall cladding on buildings.
– L1B Conservation of fuel and power in existing
›››
BS 5250: 2002: Code of practice for control of
condensation in buildings.
– E Resistance to the passage of sound
– L1A Conservation of fuel and power in new
BS 1202: Specification for nails.
Part 1: 2002: Steel nails.
– A Structure
– B Fire safety
BS 743:1970: Specification for Materials for Damp proof
courses.
92/2782 Floors
Building Regulations
›››
›››
87/1836 Pitched roofs - warm roof concept
– Section 7.1: 1989: Domestic floor joists.
›››
BS 5502: Buildings and structures for agriculture.
Part 23: 1990: Code of practice for fire precautions.
BRE publications
Part 42: 1990: Code of practice for design and
›››
›››
Thermal insulation: avoiding risks BR 262:2002.
construction of pig buildings.
Conventions for U-value calculations
Part 71: 1992: Code of practice for design and
– B. Anderson BR443: 2006
construction of ventilated stores for potatoes and
Building Elements: ‘Floors and Flooring’ – PW Pye and
onions.
›››
HW Harris BR 332: 1997
›››
›››
›››
Foundations, basements and external walls BR 440:
›››
›››
Part 3: 1985: Materials and components, design and
BRE Digest 311. Wind scour of gravel ballast on roofs.
workmanship.
BRE IP 17/01. Assessing the effects of thermal bridging
›››
BS 6203: 1991 (1996) Guide to fire characteristics and
at junctions and around openings in the external
fire performance of expanded polystyrene materials
elements of buildings.
used in building applications.
›››
BS 743: 1970: Specification for materials for damp
BS 476: Fire tests on building materials and structures.
BS 6229: 2003: Code of practice for flat roofs with
continuously supported coverings.
›››
proof courses.
›››
BS 5628: Code of practice for use of masonry.
2002.
British Standards
›››
BS 5534: 2003: Code of practice for slating and tiling.
BS 6398: 1983: Specification for bitumen damp proof
courses for masonry.
›››
BS 6399: Loading for Buildings
Part 2: 1987. Methods for determination of the fire
Part 1: 1996: Code of practice for dead and imposed
resistance of loadbearing elements of construction.
loads.
Part 3: 1958: External fire exposure roof test
Part 2: 1997: Code of practice for wind loads.
Part 3: 1988: Code of practice for imposed roof loads.
62
References
›››
›››
BS 6515: 1984 (1996) Specification for polyethylene
European standards
damp-proof courses for masonry.
›››
›››
›››
›››
›››
buildings.
structures against water from the ground.
Part 3: 2000: Roof drainage, layout and calculation.
BS 8103 Structural Design of low-rise buildings.
›››
buildings - Factory made products of extruded
investigation, foundations and ground floor slabs for
polystyrene (XPS) specification.
›››
products and building elements.
Part 1: 1997: Code of practice for design and
Part 1: Classification using test data from reaction to
construction.
fire tests
BS 8203: 2001 Code of practice for resilient floor
BS 8204: Screeds, bases and in-situ floorings.
›››
– Heat transfer via the ground – Calculation methods
›››
BS EN 13789: 1999: Thermal performance of buildings Transmission heat loss coefficient - Calculation
cement sand levelling screeds to receive floorings.
method.
BS 8215: 1991: Code of practice for design and
International standards
›››
BS EN ISO 6946: 1997 Building components and
building elements – Thermal resistance and thermal
installation of damp proof courses in masonry
transmittance – Caculation method.
construction.
›››
BS EN 13370: 1998 Thermal performance of buildings
Part 1: 1999 Code of practice for concrete bases and
surfaces.
›››
BS EN 13501: Fire classification of construction
BS 8110: Structural use of concrete.
Part 2: 1999: Code of practice for concrete wearing
›››
BS EN 13164: 2001 Thermal insulation products for
Part 1: 1995: Code of practice for stability, site
coverings.
›››
BS EN 12056: Gravity drainage systems inside
BS 8102: 1990: Code of practice for protection of
housing.
›››
Part 4: 2001 Installation
BS 8000: Workmanship on building sites.
Part 4: 1989: Code of practice for waterproofing.
BS EN 1264: Floor heating. Systems and components.
BS 8218: 1998: Code of practice for mastic asphalt
Other publications
roofing.
›››
›››
CP 1018: 1971 (1993) Electric floorwarming systems for
use with off-peak and similar supplies of electricity.
CIBSE Guide A (1999)
DEFRA/DTLR Robust Details – Limiting thermal
bridging and air leakage: Robust Construction details
for dwellings and similar buildings. 2002
›››
NBS Domestic Heating Compliance Guide: 2006
STYROFOAM Solutions
63
Recommendations
The STYROFOAM range of blue extruded foamed
polystyrene insulation products includes FLOORMATE,
ROOFMATE, WALLMATE and PERIMATE.
STYROFOAM products contain a flame retardant additive
to inhibit accidental ignition from a small fire source.
STYROFOAM is, however, combustible and if exposed to an
intensive fire may burn rapidly.
During shipment, storage, installation and use STYROFOAM
products should not be exposed to flames or other ignition
sources.
Fire classification is based on small-scale tests, which may
not reflect the reaction of the products in its end use state
under actual fire conditions.
STYROFOAM products should, when installed, be
adequately protected from direct exposure to fire.
Recommendations about the methods, use of materials
and construction details are given as a service to designers
and contractors. These are based on the experience of Dow
with the use of STYROFOAM products. Any drawings are
meant only to illustrate various possible applications and
should not be taken as a basis for design. Since Dow is a
materials supplier and exercises no control over the
installation of STYROFOAM products, no responsibility is
accepted for such drawings and recommendations.
In particular, no responsibility is accepted by Dow for the
systems in which STYROFOAM is used or the method of
application by which it is installed. The legal obligations of
Dow in respect of any sale of STYROFOAM products shall
be determined solely by the terms of the respective sales
contract.
66
Notes
The information and data contained in this brochure do
not represent exact sales specifications. The features of the
products mentioned may vary. The information contained
in this document has been provided in good faith,
however it does not imply any liability, guarantee or
assurance of product performance. It is the purchaser’s
responsibility to determine whether these Dow products
are suitable for the application desired and to ensure that
the site of work and method of application conform with
current legislation. No licence is hereby granted for the use
of patents or other industrial or intellectual property rights.
If Dow products are purchased, we advise following the
most up-to-date suggestions and recommendations.
STYROFOAM Solutions
67
Dow Chemical Company Limited
Building Solutions
2 Heathrow Boulevard, 284 Bath Road
West Drayton, Middlesex UB7 0DQ
Tel:
Fax:
020 8917 50 50
020 8917 54 13
Internet: www.styrofoameurope.com
®™* Trademark of The Dow Chemical Company ("DOW")
or an affiliated company of Dow
UK-291-UK-628-0305