Harsh conditions breed innovative housing designs

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In Nunavik, the vast region of Quebec north of the 55th parallel, extreme weather conditions present designers and builders with some formidable challenges. Violent winds sweep snow into massive snow banks, and the slightest defect in a building's insulation can make it prey to the icy cold.

On average, the heating season in Nunavik is twice as long as in Montreal. The permafrost and sensitive clay soils become unstable when warmed by heat loss from buildings above. There are no community water and sewer systems, so each one must have its own drinking water, tank and sewage holding tank.

Since 1980, the Societe d'habitation du Quebec has built almost all of the houses in 14 Inuit villages in Nunavik through a joint social housing program with Canada Mortgage and Housing Corporation. SHQ's sustained research, intensive consultation with Inuit communities, detailed design and close monitoring have produced designs that provide northerners with safe, durable, comfortable housing.

SHQ has solved the crucial question of warmth through an oil heating system that meets the harsh local conditions, and a well-sealed and insulation "envelope." The wood-frame buildings have a plywood shell as protection against the cold. Behind this exterior cladding, an air barrier and an inner vapor barrier prevent cold outdoor air or warm, moist indoor air from passing through the walls.

Another of SHQ's innovations is a subfloor inside the building that creates a pocket between the floor and the cold air outside Air ducts in this space neutralize cold conduction through the insulation so that ground-level floors remain comfortable even under the worst conditions.

The problem of shifting permafrost, which can bend or twist the frame of a house, is partially solved by mounting the building on a steel frame with adjustable jacks. In addition, the building frame rests on compact granular backfill which acts as a pad to spread the weight of the house. Vegetation is left intact under this pad as a separate layer between the gravel and the clay soil. The vegetation's insulting effect tends to stabilize the damp soil.

Working in co-operation with industry on the issues of water and sewage, SHQ came up with polyethylene holding tanks that minimize volume and make for easier maintenance. The Societe also introduced a system to connect delivery trucks with both types of tanks, to facilitate filling and emptying from outside. To prolong water supply, all taps are fitted with flow reducers, and toilets are installed the use the least possible amount of water.

The social needs of northern Native families have also been an important consideration in SHQ's housing design. Most Inuit families have many children, and often grandparents, living in one home. Because they spend much of the long winter months indoors, they need houses that not only are warm, but well-lit, well ventilated and spacious enough for all family members. SHQ's design therefore features larger-than-usual bedrooms, and windows with panoramic views. In addition, houses have lots of cupboards and a spacious vestibule that can hold a freezer as well as numerous boots and coats.

continually adapting and improving its system, SHQ has become a leader in northern building technology. More and more of what were originally SHQ innovations are now common practice throughout the north.

For well-considered innovations that meet the North's many particular demands, SHQ won a 1994 CMC Housing Award in the Technology and Production category. The theme of the 1994 awards was Sharing Successes in Native Houses.