First time homeowners get a retrofit upgrade.

This ranch house in a western suburb of Boston, the first home for a couple with two small children, was an ideal candidate for a major upgrade. Its failing siding, obsolete windows, ancient boiler, and beat-up roof — coupled with near-perfect south-facing orientation — made it a poster child for NSTAR's deep energy retrofit pilot program. NSTAR's generous funding stretched the homeowners' limited financial resources just far enough to make the project possible. Additional help came from Cambridge HEET, who became enthusiastic enough about the project to convince a large team to leave their Cambridge home base for a weekend to help the homeowners super-insulate the basement.

Framingham Ranch Retrofit

Byggmeister's Solution

The initial HERS rating for this project was 135, meaning that it's about 35% worse than code. It was modeled to use about 208 million Btus a year in total energy for all uses, or about 75,000 Btu per square foot per year including the unfinished basement.

At the end of the project, we were able to get that consumption down to an anticipated 63 million Btus — about a 70% reduction. The anticipated usage is about 23,000 Btus per square foot per year, which is less than one half the New England average for a single-family home of this age.

The mechanical system consists of Fujitsu air source heat pumps, a Fantech SH704 heat recover ventilator, and an electric resistance water heater. The weak link in this system is the water heater, but it's nonetheless a good interim measure, because, until the homeowners are in a position to install either a solar thermal system or possibly a heat pump water heater, the alternatives included propane (expensive) or retaining the oil boiler just for hot water (even more expensive). With prudent daily usage, domestic hot water does not have to represent a major energy use.

Project Location

Framingham, MA