The design and construction of C.K. Choi predated the widespread use of green building rating systems; however, environmental considerations were a key priority for the design. Along with the salvaged Douglas-fir timber, 100 per cent of the distinctive red brick cladding was sourced from a demolished building in downtown Vancouver. Other salvaged components include office doors and frames, washroom sinks and electrical conduits. Nearly 95 per cent of the construction waste was diverted from the landfill, an extraordinary achievement.
Additionally, the C.K. Choi was designed and detailed for a 200-year expected building life, with a flexible interior design to accommodate change over time.
Environmental innovations
- The building was constructed using materials that are recyclable or recycled, including bricks from demolished buildings and wooden beams from UBC’s Old Armouries.
- Water is preheated using waste heat from an existing steam line.
- Cooling and air exchange is provided by 100 per cent natural ventilation. Atriums ventilate different parts of the building through a stack effect. High ceilings and windows that open also take advantage of natural ventilation.
- Offices are placed to optimize natural light, so the building requires less than one-third the artificial lighting typically used in an office building. Daylight sensors automatically dim indoor lighting.
- Its energy-efficient design reduces UBC’s electricity use by 192,000 kilowatt-hours a year, the equivalent of the amount of energy used annually by 19 single family homes. This provides a savings to the university of $9,600 a year.
- Waterless, odourless composting toilets require no sewer connections and produce fertilizer for the garden.
- Recycled grey water from sinks and captured rain water is used for landscape watering, cutting water consumption in half.
- Landscape design by Cornelia Hahn Oberlander includes gingko trees, known for their ability to clean the air of pollutants.
REDUCING IMPACT AND CONSUMPTION
The component of this building that has piqued the most interest is unquestionably the use of composting toilets. From a water conservation perspective, the system not only saves all the water that would be used for flushing a conventional toilet, it also reduces the wastewater volume sent to the sanitary sewer system by a similar amount.
This waterless toilet system enabled the building to be disconnected from the sanitary system. An objective of the continually ventilated composting toilet system is to reduce the volume of waste by up to 90%, and produce a humus-like product that is rich in nitrogen and other useful elements. Researchers and operations staff have monitored the system since installation and have found that while these toilets have achieved their water conservation objectives, the solid and liquid outputs that are produced need to be handled differently than originally intended in order to destroy potential pathogens.
EMBODIED ENERGY IN CONSTRUCTION
Reused heavy timbers from the Armouries Building previously located across the street and reused red brick cladding from the streets of Vancouver give the Choi Building an aesthetic that is rich in history and energy efficiency. Many additional reused and recycled materials are also incorporated in the building.
The exact total of energy saved from extraction, transportation, refining and production of these materials has not yet been tallied. This number is expected to be substantial as it is estimated that more than 50% of the total materials are reused or recycled. Benefits in reduced greenhouse gas emissions are important as are the savings to the earth’s limited supply of natural resources.
OPERATING ENERGY OVER TIME
Inside the Choi Building, spaces are so filled with daylight that the power consumption for lighting is less than half that required for typical office buildings. Offices have manual light switches; however, controls systems dim lights if adequate daylight is available or turn off lights if a room is vacant.
Operating energy is also reduced by the elimination of a traditional ducted air system. The building relies on natural ventilation with a few fans to assist when necessary. Operable windows and fresh air vents under each window allow a continual flushing of fresh air through the building. The cool fresh air rises as it warms through a series of high atria. When the warm air exits the building through louvres high in the atria, fresh air is simultaneously drawn in through the window vents. In total, the energy saved from the Choi Building in one year will power four Vancouver residences.
LIVEABLE WORKING SPACE
For any building to achieve longevity and in turn be sustainable, it must be a place where people like to work or live. The occupants of the Choi Building enjoy natural daylight to work in and 100% fresh air at all times. Air quality within the building is improved through careful selection of building materials, finished products and construction practices. For example, the carpet is laid without adhesives, millwork is constructed from formaldehyde-free materials and finishes are solvent-free, low emission products. Features such as direct venting of the copy machines areas help to maintain good air quality over time.
Make sure to visit all of the features of the building before moving on to the next stop.
General Information
Uses of Wood in the Building
Sustainability Features
