Next to those designed and built by South Mountain Co., the most energy efficient houses on MV are being built by Habitat for Humanity. They are dedicated to permanent affordability for their owners. In the past, HfH often was the recipient of donated products that were sometimes on the low end of energy efficiency, such as inexpensive windows and low efficiency heating and hot water equipment. On MV, the forward thinking folks who operate HfH are, with some detailing help from SMC, building super insulated homes that are very airtight. I help with QA, testing the houses with blower door and fog machine or IR camera. The first house at Bailey Park Rd. was 175 cfm50 at the stage of windows and doors installed and most of the roughing done, but no drywall. In the next month they'll be ready for a final test. Today we tested the shell at the second house they are building there, with window and door openings poly'd off. It was just about 300 cfm50 with the air barrier being one layer of taped polyiso foam on the walls and roofs. The house is a kit, which is all T&G pine inside, a potentially very leaky strategy.
With volunteer workers, they're building a house tighter than almost all the pros do here. The beneficiaries will be the owners. The mechanical system is mini split heat pumps, far less costly to operate than fossil fuel equipment. Thanks, Habitat, for leading the way to permanently affordable housing.