At a moment of cresting anxiety about both climate change and carbon pricing, the city of Vancouver is experiencing a bracingly optimistic revolution in green building design, one that will deliver significant reductions in the amount of energy that escapes from leaky, poorly insulated mid- and high-rise apartments.
In the past two years, Vancouver has approved two so-called “passive house” high-rise projects – a 48- and 43-storey pair of towers designed by Robert A.M. Stern for Landa Global Properties and Asia Standard Americas, and a 60-storey project that will be designed by Tom Wright of WKK Architects for Henson Developments. The latter will be the world’s largest passive house development.
Beyond these showcase ventures, the city’s construction pipeline currently includes 2,200 units of these superinsulated, ultralow energy residential units spread across 49 projects, representing a total of more than two million square feet of space.
The story behind this remarkable surge offers a case study in how the right combination of smart planning regulations, ambition municipal targets and market-ready green building technologies can trigger rapid change in a sector that produces 40 per cent of all carbon emissions. For governments looking to cut emissions, such moves represent “low-hanging fruit,” says Monte Paulson, a passive house specialist at RDH Building Science.
The passive house approach, described as the industry’s most rigorous voluntary energy-based standard, traces back to German innovations in building design. The concept is to build rigorously airtight, heavily insulated structures that use components such as triple-pane windows and heat recovery pumps to minimize the loss of heating and cooling. Energy is exclusively renewable (i.e., high-efficiency gas furnaces must be replaced with electric). And all “waste” heat escaping through drain water and ventilation fans is captured and recycled.
This standard also eliminates commonplace design flaws that dog many high-rises, such as so-called thermal bridges – i.e., concrete floor slabs that include exterior balcony space and serve as a conduit for heat loss.
To qualify, a building must use no more than 15 kilowatt hours of energy for each square metre a year – a fraction of more typical energy consumption levels in new projects (100 to 150 kWhr/m2).
While passive house undertakings remain more expensive to build, they are far more economical to maintain because heating and cooling costs can be very low. “They’re sold on the basis of comfort and ‘good-for-the-planet,’” says architect Scott Kennedy, a principal at Cornerstone Architecture, which designed Vancouver’s first mid-rise passive house, a 85-unit rental project known as The Heights that was developed by Eighth Avenue Properties and opened a year ago.
The Heights, Mr. Kennedy says, “was hugely influential” in the way the City of Vancouver’s thinking about passive house has shifted.
Under former mayor Gregor Robertson, Vancouver council set a target requiring all buildings to achieve zero emissions by 2030. The city, which also wants to eliminate gas heating, then adapted its building standards to require new projects to commit to designs with significantly reduced carbon footprints.
While the passive house standard remains optional and far exceeds Vancouver’s most stringent green building requirements, city officials, at the prodding of designers such as Mr. Kennedy and Mr. Paulson, agreed to provide incentives in order to prime the pump and therefore create a foundation of experience with the techniques required.
For example, because passive house buildings have thicker walls and therefore reduced saleable floor space, they produce less return on investment than a more conventional structure. To eliminate that penalty, the city offered passive house projects a 5-per-cent density bonus. In neighbourhoods with high property values, that incentive can translate into either larger apartments or as many as two or three more units in a 100,000 square-foot project. “That five per cent got a lot of my clients across the line,” Mr. Kennedy says.
Mr. Pander points to other policy moves meant to stoke this kind of design, including a training partnership with the B.C. Institute of Technology that will expand the ranks of Lower Mainland contractors, planners and skilled trades who are certified in the techniques for building passive house projects.
The city has also established a knowledge exchange forum, based on models in New York City and Brussels, which allow builders, planners and architects to share insights on such projects so they’re not reinventing the wheel with each one.
Lastly, Vancouver’s economic development commission is looking at ways of fostering the emergence of a network of local suppliers that can manufacture or distribute components such as windows and heat pumps for these low- or no-emission buildings. A report released earlier this year projects that the local market for green building materials will top $3-billion over the next dozen years as the energy and emission standards for new or redeveloped projects become increasingly stringent.
The provincial government, for its part, has revamped its building codes to allow municipalities outside Vancouver to provide incentives for developers willing to commit to one of four energy performance targets that exceed minimum standards.
The City of Toronto, in the latest version of its Green Standard adopted a year ago, has set out a similar program with four stepped performance targets combined with incentives, including 10-per-cent to 15-per-cent reductions on development charges, says Lisa King, a senior environmental policy planner. A number of inquiries have come in since last May. At least one non-profit project, a childcare centre, will meet the most demanding of the city’s performance “tiers” while 10 others mixed-use projects will be approved for the second level.
Ms. King says the uptake in the past year has been very encouraging, but adds that because Toronto’s revamped Green Standard is newer than the comparable program in Vancouver, there are fewer completed projects to date.
Back in B.C., Mr. Paulson points out that the City of Vancouver’s leadership has attracted interest from many other jurisdictions and his firm is already taking on clients in places such as Boston. With a growing roster of passive house projects that run the gamut from high profile high-rises to garden-variety mid-rises, he says this once aggressive design standard has become increasingly, well, standard.
“The news now is that it’s not news,” Mr. Paulson says. “For me, that’s the exciting part.”
This article is part of an occasional series about recent advances in sustainable design and construction.