Home building pros in Vancouver, British Columbia, which as been dubbed the most expensive city in North America, are keenly aware of the high price of housing in their city. Cost is almost always an issue for new home and remodeling projects in the city on the southwest coast of Canada, which is also routinely ranked high for livability in the categories of healthcare, culture, environment, education, and infrastructure.
So it was no surprise to architect James Tuer that going over budget was not an option when designing the House and Laneway House infill project located near a busy commercial corridor in downtown Vancouver. His empty nester clients had a respectable budget of $275 a square foot (U.S.) but were adamant about not spending a penny more; they had fired their original architect for not adhering to that amount. They also had a preference for modern design and a long list of requirements for the tiny dwelling, including a home office, studio space, a guest room that could be repurposed when vacant, and a kitchen that would lend itself to family gatherings.
The owners were also committed to sustainable principles, so Tuer turned to passive environmental control systems that wouldn’t break the bank. His approach focused on simple roof shapes for harvesting rainwater and a focus on energy efficiency through highly insulated walls. To provide extra living space, Tuer added a “laneway house” to the backyard just steps from the main house (see Urban Outbuildings story at left).
The high-performance building shell includes exposed concrete exteriors and a second wood frame wall on the interior, creating a double wall that holds 14 inches of open-cell foam insulation. The walls on the second floor are built from 2x10 plates and staggered 2x4 studs. Standing-seam siding creates a durable exterior cladding system that contrasts with colorful fiber cement panels that align with the vertical window patterns, Tuer says.
Rainwater from both structures is directed to a 600-gallon, below-grade cistern that provides drip irrigation to the lawn-free yard. In designing this catchment system Tuer and team successfully lobbied city officials to re-write a bylaw that discouraged rainwater harvesting and required a commercial-grade back-flow preventer at the property line.
To save money, project planners went through a detailed cost analysis of the building footprint, Tuer says. “It’s a rectangle with only one small push-out when we detailed the large box window. The roof is also very simple being a shed roof aligning with a center load bearing wall upstairs.” The house was framed in about four weeks.
At the heart of the two-bedroom home is a 12-foot staircase that wraps around a freestanding concrete fin wall and acts as natural air conditioner in the summer. Its thermal mass absorbs cool air when the windows are open in the evening and then radiates it back during the day, Tuer says.
Other sustainable features include:
--Formaldehyde-free birch plywood and 25 percent recycled content gypsum wall board finishes
--Energy star appliances and wood windows with average U -value of 1.4
--Low-VOC paints and adhesives
--An integrated, gas-fired, on-demand hot water and hydronic in-floor radiant heat system that is pre-plumbed for solar assisted evacuated tubes