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first_imgMontreal firm designs a prototypeOne possible solution to this regional housing shortage is a duplex designed by Alain Fournier and EVOQ, a Montreal-based architectural firm specializing in buildings for Inuit and First Nations peoples in arctic regions.Fournier’s team and the four regional organizations with a role to play in providing new housing originally hoped to design housing that would be able to meet the Passive House standard. But that didn’t prove realistic.“The idea was to have the house be Passive House certified, or at least to obtain the objectives of Passive House,” Sami Tannoury, an EVOQ associate architect who worked on the project, told GBA by telephone. “But after the development phase where the engineers calculated the energy reduction, we could not obtain that objective, which was 90% [less] energy consumption compared to building code. It was too deep an envelope. It was not realistic.”The duplex prototype will use 8.5 times as much energy as a Passive House building, Alain Fouriner told NewsDeeply, but still far less than a typical duplex in the region: $3,327 (Canadian) to pay for heat vs. $5,500 to $7,000. RELATED ARTICLES Dealing with permafrostThe 2,540-square-foot building, with two 2-bedroom apartments and a separate 193-square-foot mechanical room, is built on steel pilings driven into the permafrost, a departure from typical construction in the region. To prevent buckling, permafrost must be shielded from the heat leaking from the foundation of a conventional building.Ordinarily, Tannoury explained, houses in the Nunavik region would be constructed over thick gravel bases that keep heat migrating through the floor from melting the permafrost. Houses are supported by height-adjustable stilts sitting on concrete bases bedded in the gravel.Sometimes buildings in northern regions are constructed over thermosyphons, passive systems that that prevent the permafrost from melting and heaving.But on the Quaqtaq project, designers borrowed the steel-piling technique used in other parts of far northern Canada, in part to save the expense of placing a very deep bed of gravel on the steeply sloped building site. Steel piles are connected to a steel frame, which supports a wood flooring system and wood structural walls.Both floor and walls are insulated with blown-in insulation, with a layer of rigid foam insulation added on the outside to reduce thermal bridging. The truss roof is insulated with the same material. EVOQ did not offer details on what types of insulation were used, but said the roof was insulated to R-59, the exterior walls to R-54 and the floor to R-57.Windows are Passive House-certified triple-pane units, and the house is ventilated continuously with a heat-recovery ventilator. Tannoury said that the intent had been to test the airtightness of the building with a blower door, but the government had not budgeted for an outside agency to do the work and the in-house test proved “inconclusive.”Heat is provided by a hydro-air system system which uses an oil-fired boiler to make hot water and air to distribute the heat. The system corrects a long-standing problem engineers had with conventional forced-air systems in the region: even the smallest available furnaces were oversized for the small dwellings.“You heat a lot for 10 minutes and then you stop heating,” Tannoury said. “You start and stop. You start and you stop. The comfort level is not that great.”With the hyrbid system, the air handler can run for long stretches without overheating the house because the water temperature can be matched to the heating load more precisely. Also, the system is zoned, and the boiler can be used to preheat air entering the HRV. These challenging conditions are what face regional planners working to solve a housing crisis that has plagued Nunavik for years, according to an account posted at the website NewsDeeply. The Kativik Municipal Housing Bureau estimates that Nunavik needs more than 1,000 homes, and the Canadian government has earmarked up to $177.7 million (Canadian) to pay for them. The question is what kind of housing to build. A Passivhaus Design for Alaska’s Frigid ClimateA Report from the Passivhaus Front LinesIs Passivhaus Right for a Cold Canadian Climate?Alaskan Glaciers Are Rapidly Melting It’s hard enough to design a house for Minnesota, say, or Maine, where a family can stay comfortable all winter without spending a small fortune on heat. Imagine the same challenge in a region where winters are much longer and much colder, and building materials not nearly as easy to come by.You would have a place like Quaqtaq, one of 14 villages in the Nunavik region of northern Quebec, a remote and sparsely populated area larger than the state of California. At 58 degrees north of the equator, Quaqtaq averages 15,500 heating degree days a year, more than double the total in Minneapolis. In just three months – January, February and March – the number of heating degree days, 6,521, is roughly the same as the yearly total in Portland, Maine.Low temperatures aren’t the only difficulty. Houses are built over permafrost, unpredictable and perpetually frozen earth that can shift and heave when conventional houses are built on top of it. There’s no such thing as a simple slab-on-grade construction. Plus, the region’s native Inuit have cultural expectations for housing that are strongly rooted in history and environment, and may not be compatible with typical housing. Serving the Inuit communityComfort and lower heating bills were important aims, but so was building in features that met Inuit cultural needs.“We work very hard on the cultural integration in our projects,” Tannoury said. “It’s very important to us to have them build an environment that represents their aspirations and their culture.”The design process began with a charrette, a meeting involving all principals in the project. The resulting list of cultural needs for the Inuit people was built into the prototype. One of them is a “cold porch,” an unheated space something like an airlock or mudroom that protects the main entrance from the harsh weather of the region and gives occupants a place to store hunting and fishing gear. It’s equipped with a stainless steel counter that can be used to clean fish and equipment or work on animal skins.The duplex also got a second egress, not typical for construction in the region, because fire protection services can be relatively slow, and the Inuit have a fear of being trapped inside a burning building.In the kitchen, counters are mobile so they can be pushed out of the way to accommodate traditional food preparation and traditional suppers, which are taken sitting on the floor, Tannoury said.There’s no telling yet whether the duplex will be adopted as a template house for the Nunavik region. But according to Tannoury, performance data are being collected and eventually the information will be summarized in a post-mortem that can be used to develop regional housing programs.“It’s my hope that something else will be designed, taking lessons learned from this,” Fournier told NewsDeeply. “I would be very surprised if someone said, ‘Oh, we hit the nail on the head.’”last_img read more