Innovative Eco-Housing Design in Canada's High Arctic
Canada's newest Territory, Nunavut has some of the most serious housing issues in Canada. Consider these statistics compiled by the Nunavut Housing Corporation (NHC): public housing makes up the majority of housing occupied by Nunavummiut; almost 50 per cent of households are overcrowded and/or in need of major repair. If more housing were made available, NHC estimates that over three and a half thousand people would move out of below standard housing. New housing will also provide the 4 percent of couch-surfing Nunavummiut an opportunity to be able to find their own place to live.
The harsh climate, remote geography, and lack of built infrastructure in the North significantly contribute to the extremely high costs of and lack of adequate housing in the Territory. Many studies have correlated inadequate, unsuitable, overcrowded housing with community and social well-being. Overcrowding, for example, can have direct health impacts on infants; can contribute to the transmission of infectious diseases such as tuberculosis and can exacerbate emotional duress. It's clear that an increased investment in suitable northern housing is an important ingredient to enhancing and supporting the physical, social, emotional and spiritual health of Nunavummiut.
The creation of new northern social housing requires innovative solutions. In 2009, the Government of Nunavut (GN) received $100 million over two years under the federal government’s Economic Action Plan to build affordable housing. Together with Canada Mortgage and Housing Corporation (CMHC), the Nunavut Housing Corporation developed a plan to spend part of these dollars on an innovative housing project to increase the supply of housing in the territory while reducing the consumption of energy, including heating fuel. The project team developed strict requirements for a winning proposal. Using structural insulated panels (SIPs), the design needed to include:
an R-50 floor, R-40 walls, and R-50 roof;
the incorporation of the structural elements within the panel;
an integrated vapour control layer;
air leakage control to 0.50 ACH@50Pa without reliance on caulking or spray foam;
the ability to meet the highest wind and snow loads in Nunavut;
the capability of being handled by hand or machine; and
a means of cantilevering the floor beyond the foundation.
Ottawa-based Kott North provided the winning innovative design for this multi-million dollar housing development. The firm designed the construction details of the SIP’s system for the house to provide maximum thermal efficacy, ease of construction, and high durability to meet the climate and energy-efficiency challenges of Nunavut. Kott’s Tuktu panel included:
an expanded polystyrene core with Oriented Strand Board (OSB) skins;
use of urethane glue having specific vapour control characteristics to glue the OSB skins to the insulated core;
structural Nascor i-joist splines;
a layer of expanded polystyrene as a thermal break for all structural components;
soft foam gaskets at the panel joints to control air leakage; and
peel and stick membranes on panel joints’ airtight connections between panels.
The result was a panel capable of addressing Nunavut’s harsh conditions and unique building challenges. The Tuktu SIP uses modern design principles, which resulted in an incredibly tight building envelope of0.19 ACH @ 50 Pa, less than one-seventh the maximum allowable air leakage for an R2000 home(1.5 ACH @ 50 Pa)—a leading benchmark for energy-efficient construction in Canada. In total, 142 of these housing units were built in 19 communities across the territory. Continued energy monitoring and analysis of heating bills will help to confirm that these houses are actually meeting the energy-efficiency requirements specified by the NHC. And one day soon these northern inspired technologies may offer the possibility of contributing to a better environmental footprint in the South.
Check out my full report on Sustainable Northern Housing Options in Canada's North for free here.
