Glossary

Blower Door Test: Homes are tested for air tightness. After insulation, a large fan in a nylon door is set in the front door opening. This fan is connected to a computer and exhausts air from the house until the interior pressure is -50pa. This measures total air changes per hour (ACH).

Double Wall Frame: Framing two exterior walls, one inside the other. This allows for increased insulation and minimizes thermal bridging.

Durisol: Insulated concrete form made of 100% recycled wood chips and Portland cement. The blocks are stacked like Legos and poured full of concrete. The block's mineral wool insulation is on the exterior side of the wall so the concrete acts as a huge thermal mass inside the building.

Hardie Plank: A very durable and stable cement based siding.

Heat Recovery Ventilator (HRV): Whole house ventilation. It brings fresh air from outside to living areas and bedrooms, while exhausting air from kitchens and baths. Heat recovery units are capable of preheating incoming air from the outgoing exhaust.

Net Metering: An agreement with a utility supplier that any surplus electricity generated on site can be sent to the grid. Accounts will be credited for any electricity generated beyond usage.

Oriented Strand Board (OSB): An engineered wood product formed by orienting strands of wood for strength and durability. A panel is similar to plywood.

Photovoltaic (PV): Solar panels that generate electricity. Electricity can then be stored in batteries or net metered.

Structural Insulated Panel (SIP): An engineered panel of rigid foam sandwiched between two structural OSB panels. These highly insulated panels are fabricated off site and assembled on site.

Solar Hot Water: Solar panels that heat domestic hot water for home use.

Staggered Studs: Used in double wall framing. The inside studs are offset from the exterior, allowing insulation to be placed completely over the exterior stud and eliminate thermal bridging.

Thermal Bridge: Non-insulated material that transfers energy through conduction. For example, in a 2x6 framed wall, the studs and plates go from inside the building to outside. In winter, this stud will be colder than the insulated cavity directly next to it.

Thermal Mass: A dense material (concrete, stone) that stores thermal energy and releases it over time. Think of a sidewalk in the summer that is heated all day by the sun and is still warm in the evening. In homes, concrete floors or walls can be used to store warmth, generating very minimal temperature swings in the home.

Tulikivi: Soapstone Masonry Heater from Finland. Super efficient: a fire is burned hot and fast, flue gasses circulate through the heater and warm the soapstone. The soapstone releases that heat over twelve to twenty-four hours.