The builders estimate that less than 1.3 kWh/square foot (14 kWh/square meter) of energy will be needed annually to supply the necessary power and hot water to the household. The home was insulated using high performance cellulose insulation and pressed wood fiberboard insulation, which are both non-toxic, resistant to mold, and deter rodents. The home is also fitted with vaporproof membranes, which eliminates condensation in the summer and facilitates drying in the winter.

The home also takes advantage of passive heating and has a green roof, which works to insulate the home. The green roof is also angled and works to help increase the size of the main sunlight-facing window during the winter. The home is fitted with an underfloor and in-wall heating system. Some of the energy required to power both of these heating systems comes from a small gas boiler with a buffer tank, though other forms of temperature control are also employed.

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stairs

upstairs

bath

The home is also equipped with an earth-to-air heat exchanger, which uses the ground temperature to heat the house in the winter, and cool it in the summer. The living room is fitted with a biomass chimney fueled by wood chips, which is connected to the buffer tank. To get fresh air into the home, the builders installed a mechanical ventilation system with heat recovery, which, according to the designers, is able to retain 85 percent of the heat in the outgoing air.

The home is also fitted with a rainwater catchment system with an underground storage tank, and the water collected in this way is used to irrigate vegetation and crops. In the near future, they are also planning on installing a PV array to offset some of the home’s power needs.

plan

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diagram