Team Canada Solar Decathlon 2011

TRTL – Technological Residence Traditional Living
Canada’s Entry into the U.S. Department of Energy’s Solar Decathlon 2011 Competition

Mission
TRTL is a celebration of Canadian innovation and cultural diversity. Our partnership with the Native communities of Treaty 7 draws on respect, equity, and inclusion to raise awareness of critical Native housing issues and explore holisitic solutions.

Design Philosophy
TRTL is pronounced ‘turtle’, short for Technological Residence Traditional Living. Our design philosophy is based upon a triple-bottom-line approach to sustainability – including environmental, social and economic factors. Cutting-edge green building methods and Native cultural design considerations are integrated in an affordable home that meets contemporary needs and interests.

Traditional Inspiration and Market Appeal
Inspired by the Tipi, TRTL‘s rounded form, east-facing entrance and solar power acknowledge the sun as a traditional source of energy and life. This fosters positive spiritual and spatial energy, and a sense of Native identity in the home. Use of local natural materials and colors both outside and inside further this sense of tradition, as do local arts and crafts of the Treaty 7 peoples. Specific traditional items used in TRTL include a buffalo robe and skull, mocassins, pendleton blankets, and backrests.

The interior is also draped with canvas, like that used to make modern tipis. This is decorated with a winter count, a traditional pictographic story that details the life of the residents, their place in the community, and the home’s creation process. Cedar siding, cork flooring, and colors based on the four elements bring the home to life, as part of the greater natural order.  TRTL is being validated and blessed through 4 traditional ceremonies. The home has been given the Blackfoot name Spo’pi – meaning ‘turtle’ or ‘lives on stilts’.

For decades, cultural considerations have been notably absent in Native housing design. While TRTL is designed in collaboration with Native Treaty 7 communities, many other Native groups across North America also use the tipi, and favor local and natural materials and colors. Thus TRTL’s traditionally-inspired design will resonate with a broad market. Furthermore, many non-Native people have expressed strong interest in the home’s beautiful form and practical functionality.

Solar Power
TRTL’s 8.7kW solar array is tuned to perform at 95% efficiency for the region, ensuring the home produces as much or more energy than it consumes per year (annual net zero energy balance).  A system of microinverters maximizes per panel output, and allows for individual panel monitoring.

Decentralized energy represents an important opportunity, especially for remote Native communities, where infrastructure and energy costs are high and rising. Solar power may not only alleviate operating costs, but also become a source of revenue for future housing and infrastructure initiatives.

Health, Safety, Durability and Affordability
TRTL’s ‘shell’ consists of a steel sub-frame wrapped in Titanwall SIPs (structural insulated panels), which are made of magnesium-oxide and expanded polystyrene. Applying them consistently across the building envelope minimizes thermal bridging (unwanted transfer of thermal energy through the structure). The SIPs are extremely resistant to fire and mold, providing a healthy and safe environment that allows for high quality of life. The SIPs are also very durable, reducing maintenance costs and providing a projected lifespan is 75-100 years. Native communities can view TRTL as a long term investment, freeing up revenue from maintenance and replacement to reinvest in new initiatives.

TitanWall SIPs were selected in direct response to high rates of fire and mould in Native communities, which currently drive an epidemic of health and safety issues (including respiratory illness, and rates of death from fire exceeding 10 times that of non-native communities).  Short building lifespans are also a key consideration, with some conventional homes lasting as little as 5 years.

Inside the home, materials and finishes have also been selected for durability, sanitation, and low environmental impact. The kitchen counter is a hard laminate, the floors are cork, and the backsplash is glass tile. Paints and varnishes with low VOC’s (volatile organic compounds) also help to ensure high indoor air quality. The robust design is complimented by strong ventilation, conveniently and strategically located fire extinguishers, and a full sprinkler system.

Efficiency
Using resources efficiently is an important part of environmental and economic sustainability. TRTL’s efficient appliances, lighting and mechanical system are expected to use 70% less energy than that of a conventional building of the same size. An efficient washing machine, low-flow plumbing and a low-flush toilet also help to ensure efficient use of water.

The mechanical system is purely electric and powered entirely by the photovoltaic array, thereby offering reduced operating costs, and fewer maintenance needs than a solar thermal system.  An air-source heat-pump is the main mechanical component. The heat pump uses a bi-directional refrigeration cycle to move thermal energy, which is far more efficient than using a heating element to convert electricity directly into heat. The heat pump moves heat into or out of it’s working fluid – water – thereby meeting all of the home’s needs for heating and cooling air and water. A hydronic fan coil forces air through a network of pipes that carry the heated or chilled water, and then through ducts to the various rooms of the home. An integrated heat recovery ventilator captures valuable heat from exhaust air, and transfers to incoming fresh air. This is a simple, efficient, and cost-effective way to ensure comfort throughout the home.

Size, Flexibility and Demographics
TRTL is approximately 1000ft2, which is the limit for a Solar Decathlon 2011 design. In response to the high number of large families and rapid population growth in Native communities, the home includes 2 bedrooms with ample space for recreation and storage. It’s interior functionality is also highly flexible. The south half of the home is an open concept centered around the kitchen, in response to importance of family and community gathering, cooking and eating. The wall between the two bedrooms in the North is non-load-bearing; it can be easily removed to create a single large bedroom. Alternately, one bedroom can be converted to a studio, for example before starting a family, or after the kids have moved out. TRTL’s panelized design allows for rapid assembly – the home was constructed in approximately 8 weeks. The design is also flexible – it can be modified in the design phase to increase size, change location of features, and meet different geographic and climatic needs.

Home Ownership
Canada’s Indian Act dictates that reserve lands cannot be privately owned. By law, any permanent structure built on reserve lands becomes part of the land, and therefore the property of local government. This presents a challenge to private home ownership, undermining associated economic leverage.

TRTL’s preferred foundation is a screw pile. Combined with the home’s modular structure, the temporary device may facilitate private ownership on reserve lands. This would in turn provide economic leverage and responsibility for maintenance, upgrading, or starting a small business or farm. These are key steps to driving long-term stability, socioeconomic development and self-determinacy.

Coincidentally, the screw pile method is well-suited to the home’s Blackfoot name: Spo’pi (SPO-PEE) -  the Blackfoot word for ‘turtle’ literally means ‘lives on stilts’.