Download General Information Space Type Applicability All projects

5.4.1 General Information
Space Type
Applicability
All projects
Definition
For identifying space type, either the complete building method or area category
method may be used.
If lighting compliance is not performed, use either approach, but actual LPDs cannot
be entered for the spaces – the LPDs of the building match the standard design.
The allowed building types in complete building category or space types in area
category is available from Nonresidential Appendix 5.4A. The building or space type
determines the following baseline inputs:
Number of occupants (occupant density)
Equipment Power Density
Lighting Power Density
Hot Water Load
Ventilation Rate
Schedules (from Appendix 5.4B)
Units
List
Input Restrictions
Only selections shown in the Appendix 5.4A may be used.
For unconditioned spaces, the user must enter “Unconditioned” as the occupancy and
ventilation, internal loads and uses are set to zero. Compliance software shall require
the user to identify if lighting compliance is performed (lighting plans are included or
have already been submitted).
Standard Design
Same as proposed.
Standard Design,
Existing Buildings
Same as proposed
1.1.1.1 Outdoor Air Ventilation
Ventilation Source
Applicability
All thermal zones
Definition
The source of ventilation for an HVAC system. The choices are:

Natural (by operable openings)

Forced (by fan)
Units
List: natural or forced
Input Restrictions
For residential units and hotel/motel guest rooms, as designed. For all other
occupancies, as designed.
Standard Design
For residential units, set to same as proposed, for all other occupancies, set equal to
the same value for the proposed design.
Design Ventilation Rate
Applicability
All thermal zones
Definition
The quantity of ventilation air that is provided to the space for the specified thermal
zone at maximum occupancy
Units
cfm or cfm/occupant
Input Restrictions
As designed, but not lower than code minimum (default value).
The default value shall be the larger of 15 cfm times the design occupancy from
Appendix 5.4A or the conditioned floor area times the applicable ventilation rate from
Appendix 5.4A or Table 120.1-A of the Standards. .
Standard Design
The standard design outside air ventilation rate shall be the larger of 15 cfm times the
design occupancy from Appendix 5.4A, or the conditioned floor area of the space
times the applicable ventilation rate in Appendix 5.4A or Table 120.1-A of the
Standards.
Minimum Ventilation Rate
Applicability
All thermal zones, excluding unconditioned spaces
Definition
The minimum quantity of ventilation air that must be provided to the space when it is
occupied
Units
cfm or cfm/ft²
Input Restrictions
As designed, but not lower than code minimum (default value). The default value shall
be the larger of 15 cfm times the design occupancy from Appendix 5.4A or the
conditioned floor area times the applicable ventilation rate from Appendix 5.4A or
Table 120.1-A of the Standards.
For labs the minimum ventilation rate shall not be less than 6 ACH at all times.
For spaces where demand control ventilation is installed, the minimum ventilation rate
is specified by the greater of the rate in Table 120.1-A or 15 cfm times the scheduled
occupancy for that hour;
For spaces where Occupant sensor ventilation controls are installed, the minimum
ventilation rate shall be 25% of the area-based values in Table 120.1-A (e.g. 0.0375
cfm/ft2 for office) during hours when the occupancy schedule is 10% or less.
Standard Design
For spaces where demand control ventilation is required, the minimum ventilation rate
is specified by the greater of the rate in Table 120.1-A or 15 cfm times the scheduled
occupancy for that hour;
For systems serving laboratories, the airflow minimum for each lab space shall be 6
ACH.
For systems serving kitchens, the minimum outside air ventilation rate is the exhaust
air ventilation rate minus available transfer air (available transfer shall be calculated
from the building minimum outside airflow less any exhaust airflows other than kitchen
exhausts) and minus 0.05 cfm/ft2 for exfiltration
for all other spaces, the minimum ventilation rate is the same as the design ventilation
rate in the standard design.
Ventilation Control Method
Applicability
All thermal zones
Definition
The method used to determine outside air ventilation needed for each hour in the
simulation. This information is reported to the system serving the zone. The method of
controlling outside air at the system level in response to this information is discussed
under secondary systems. Options at the zone level are:

Occupant sensors: When the space is occupied according to the prescribed
occupancy schedule, the outside air requirement is equal to the design ventilation
rate; otherwise, the outside air requirement is either 25% of the minimum
ventilation rate or scheduled off (0).

CO2 sensors in the space: The outside air is varied to maintain a maximum CO 2
concentration in the space. This shall be approximated by multiplying the
ventilation rate per occupant times the number of occupants for that hour. (When
turnstile counts are used to automatically adjust ventilation levels based on
occupancy, this method may also be used.)

Fixed ventilation rate. Outside air is delivered to the zone at a constant rate and is
equal to the design ventilation rate (see above).
Units
List (see above)
Input Restrictions
As designed
Standard Design
For Title 24 compliance, if the default occupancy from Appendix 5.4B is greater than
25 persons per 1,000 ft² , set control method to CO2 sensors in the space, otherwise
set to fixed ventilation rate.