Download Edmonton, Alberta, Canada

EPCOR TOWER
Edmonton, Alberta, Canada
Building Type
Sustainable Measures
Status
Completed September 2011
The two largest sources of recycled content are found in the fly ash (SCM) content
of concrete used in the structure and in the reinforcing steel selected for its high
recycled content. Approximately CDN$11M of concrete and CDN$9M of reinforcing
steel were placed as part of the tower project. Additional sources of recycled content
include the upper tower structural steel, door hardware, and toilet partitions.
The project currently registers over 24% of combined recycled content value as a
percentage of total materials cost. Nearly all of the regional material is found in
the cementitious products such as concrete, mortar, masonry block and aggregate.
Additional sources include panel insulation and landscaping materials. The project
has documented more than 22% of the material installed on site qualifies as having a
regional composition. The project specified that, where possible, Forest Stewardship
Council (FSC) wood should be used. Trade and vendor documentation indicate that
over CDN$150,000 of FSC wood was used in the project achieving over 90% FSC
certified wood as a percentage of total new wood used.
Building Function
Office, retail
Designers
Kasian Architecture Interior Design and Planning Ltd.,
AECOM, Eidos
Development Manager
Qualico
Construction Manager
Ledcor
Site Area
8,988 m2
Gross Floor Area
95,260 m2 including parkade
Occupants
3,255
Performance Results
Net annual consumption of delivered energy
for building operations
206 kWh/m2/yr
Percentage of reduction of energy compared
to ASHRAE 90.1-04
41.4%
Net annual consumption of potable water
for building operations
0.191 m3/m2/yr
Annual use of rainwater for building operations
0.0466 m3/m2/yr
The project utilized single source bins for all major recyclable materials such as
wood, drywall, metal, paper, concrete/asphalt rubble, and general waste. Over
40 months the project has generated approximately 5,200 tonnes of waste and
has diverted more than 86% of that waste from landfill sites. Once the building is
operational, recyclables will be collected and stored in a designated area on the P1
parking level.
The building is located in downtown Edmonton and has good access to numerous
bus routes to encourage the use of public transportation. As well, secure indoor bike
storage and showers are available for building occupants. In the final build out of the
site, there will be direct connections to the Light Rail Transit system.
The ventilation and terminal systems (fan coils) have been chosen to provide a
system with a ventilation effectiveness that exceeds 1.0 and ensures adequate
distribution of ventilation air within the occupied spaces. Key features of the indoor
air quality system include over 50% occupant controls, 100% outdoor air system, and
humidity control. Daylighting was one of the key factors in selecting a window-towall ratio of 49%. High floor to floor dimensions allow daylight penetration to the core
walls. In addition, the day lighting reduces energy consumption as internal artificial
lighting power is reduced during periods of daylight.
The Epcor Tower uses dual flush water closets which have a maximum flow rate
of 6Lpf. The reduced flush is 70% of the maximum or 4.2Lpf. The building also
employs low flow urinals, low flow lavatories, and low flow shower heads. Rainwater
is captured and stored in a 725m3 tank located under the parkade structure.
Precipitation is captured from various roof levels, the balconies, and the street level
plaza areas. The rainwater is then treated and reused to flush water closets and
urinals at an estimated 4,439m3/yr.
Exterior Rendering of Epcor Tower
Courtesy of Kasian
Interior Rendering of Main Lobby
Courtesy of Kasian
EPCOR TOWER
Edmonton, Alberta, Canada
Earth Tube Schematic
Courtesy of AECOM
Station Lands Site Plan
Courtesy of Kasian
Unique Technology
Site Conditions
Epcor Tower takes advantage of a unique system of earth
tubes used to pre-heat and pre-cool the building outdoor
air. The principle of earth tubes is a geothermal exchange
between the air and the surrounding earth using a
thermally conductive material as a separation. The greater
the surface area in contact with the ground, the better
the heat transfer will be. Because the ground temperature
essentially remains constant below the frost line, the
ground can be used to heat the air in the winter season and
cool the air in the summer season. In order to maximize
the rate of heat transfer, it is ideal to flow the air at a low
velocity through the earth tubes to provide adequate lag
time for the heat transfer to occur.
Epcor Tower (Tower A) is the first building of a four block development known as Station
Lands. A multi-faceted, multi-use development, Station Lands provides more than
232,260m2 of opportunity. The project includes four high-rise towers, a multi-storey
public plaza and retail concourse, and large plate podium space rising from four to seven
storeys. Station Lands brings together commercial, retail, residential and recreational
space with a full suite of urban amenities. Expected to be completed with a 12 to 15 year
timeframe, the design enables development to be staged both horizontally and vertically,
meeting market demand and requirements for various land uses as they arise.
For this project, two vertical intake shafts run down the
exterior of the parkade walls. These intake shafts are
constructed with glycol heating lines inside the concrete
to ensure freezing does not occur. Once the shafts have
passed the lowest parkade level, they turn 90° to continue
horizontally below the parkade structure. The earth
tubes then form a loop around the building’s core before
connecting to the main tower air handling unit which
provides the rest of the conditioning.
The earth tubes themselves are built as a combination
of precast concrete pipes and poured concrete plenums
with internal columns for structural support. The plenums
are 9.5m wide and 2.5m high, with an airflow rate of
18,877L/s per earth tube. The earth tubes are designed for
the maximum load, which in Edmonton occurs in heating
mode. The desired temperature rise is from -34°C to 6°C,
6°C being the constant ground temperature below the frost
line, resulting in a 40°C delta. Using a heat transfer rate of
0.5°C/m, each earth tube needs to be a minimum of 80m in
length. The actual length of the constructed earth tubes are
116m and 97m.
Epcor Tower is a commercial office building with a stepped glass facade facing
the downtown core and river valley. Tower B is a hotel/office building providing an
opportunity for “live work” arrangement within one structure. Sitting on a two level retail
base, Tower C houses another 16 floors of office space. Tower D offers a combination of
residential uses featuring assisted living and market housing.
A low level podium development will maintain view corridors while maximizing vehicular
and pedestrian access. Circulation will be maintained with a series of above and below
grade pedestrian connections within the project, to adjacent buildings and, eventually to
municipal light rail transit. Lit by a continuous skylight, a public plaza connects the four
towers with a multi-level retail concourse.
Social, Economic, Cultural Issues
In creating this unique development for the heart of Edmonton, inspiration was found
in the Capital City Downtown Plan. The plan encourages a vibrant and attractive area
providing opportunities for people to live, work, and enjoy downtown Edmonton.
Station Lands is a creative and exciting new project celebrating the future of downtown
accommodation in a high tech and dynamic business environment.
Edmonton is the sixth largest city in Canada with a population exceeding one million.
It encompasses 67 km2, giving it one of the lowest population densities of any major
North American city. The central downtown district has a daytime population of more
than 60,000. Within adjacent neighbourhoods is a further residential population of
more than 50,000.
Station Lands is bordered by two major gateways to Edmonton’s downtown business
district - 97th Street on the east and 101st Street on the west. It is near existing Light
Rail Transit (LRT) stations and will be directly connected with future extensions of the
system. Edmonton Transit Systems (ETS) offers bus service from the downtown area to
transit centres throughout the city and adjacent communities.
In close proximity to Station Lands are numerous civic attractions including Edmonton’s
City Hall, central library, art gallery and Arts District venues such as the Winspear
Concert Hall and Citadel Theatre and the proposed sites for Edmonton’s new downtown
arena and the Royal Alberta Museum. Nearby Sir Winston Churchill Square is the city’s
premiere year-round outdoor public festival venue. More than 20,000 businesses in and
near the downtown area include restaurants, major shopping outlets, unique shops,
professional services and large public and private sector employers.