Green Me Now

This Saturday’s GreenBuildings Open House, taking place across the Northeastern United States, covers the spectrum of high-end, highly ambitious energy-efficiency retrofits to more modest alternative energy projects. In many cases, the projects were done not so much for the payback to be realized as for a demonstration of what can be done, both at the level of a homeowner and the level of architects and builders.

The annual event is arranged by the Northeast Sustainable Energy Association.

One of the high-end efforts sits in Gloucester, MA, on High Popples Rd., the 2,432-square-foot home of John Livermore. The 1973 garrison-style house last year underwent a so-called deep energy retrofit, a superinsulation of the building envelope.

Livermore, an energy efficiency consultant who did much of the work himself, says he wanted to demonstrate what can be done to reduce the carbon footprint of a suburban homeowner on a budget of approximately $50,000. “The overall goal is to reduce our home’s carbon footprint by 90%,” he says in project details presented on a green building web site.

The retrofit, which came in at $60,000, features a site-built Larsen truss wall system on the building exterior, closed-cell spray foam, high performance windows and doors, solar electric system, and solar hot water system.

The Larsen truss system is a wooden framework that provides structural strength and additional depth for insulation. Livermore attached the truss system over the existing exterior siding, which was then encapsulated with closed-cell foam insulation. By doing so, he eliminated the need to remove and dispose of the old siding. HardiPlank siding, a composite of cement and wood waste, now covers the truss.

Onsite renewable energy comprises a 4.3-kW solar electric system and a three-panel solar hot water system.

Replacement windows are Thermotec triple-pane low-E argon. Attic insulation is R-76 and includes a radiant barrier for repelling summer heat. Walls are rated at R-43, after the addition of five inches of the closed-cell foam. All lighting is now compact fluorescent and LED.