The roof uses ten-inch thick SIPs. Energy efficient windows reduce heat loss common through glazing. The home is topped with an attractive green metal roof that will last for decades and is recyclable. And in this potential “high snow zone”, Terry added snow stops to reduce snow build-up around the home’s perimeter.
The condensation and mold problems that can occur in an airtight home are eliminated with proper ventilation. Davenport says, “You either want a tipi or an airtight, well- insulated home with a ventilation control system.” The Line House uses a Venmar heat recovery ventilator. It helps assure draft-free comfort and healthy indoor air, while recovering over 90% of the heat from the indoor air being vented to the outside.
The Line House makes extensive use of fire-killed timber that was harvested and milled near Missoula. It was used as both exterior siding and interior paneling. Davenport stresses the importance of using locally produced materials when possible. “Right now, the Missoula area has an abundance of fire killed timber.” Some timber harvesters bring selected quantities from the mountains to the mills, leaving enough behind to prevent soil erosion. This helps the forest regenerate.
The high insulation values of the foundation, walls and roof, and proper air circulation, enable the home to have an even temperature throughout. There is no extreme build up of heat in the upper levels. Consequently, there is no need for air conditioning during the summer, something that is being seen more often in many Montana homes. Terry agrees that the upfront costs of building a high performance home sometimes make owners forego efficiency for air conditioning, but he says the added comfort and lower operating expenses always make that upfront investment worthwhile.