Evaluation of modifications to the Mastin double-envelope house

A double-envelope house in Middletown, RI, evaluated by Brookhaven National Laboratory personnel in 1981, was subsequently modified by the owner. The glazing in the roof was removed and replaced by skylights with only one-sixth as much area. The between-shells space was closed at the top of the north wall and at the top of the sunspace. Ducts and a thermostatically controlled fan were installed to draw warm air from the top of the sunspace and blow it through the crawl space. The house performance was re-monitored in 1983 to identify the effects of the modifications. In general, they served to reduce construction cost and improve comfort without increasing the house's low requirement for auxiliary heat.