High Performance Homes on a Budget - Images 1-8

The author's company was chosen to build a community of small, zero-energy homes. The challenge was to keep them affordable, a goal that should be met over time owing to low fuel and maintenance costs.

Wedged-shaped battens made of pressure-treated lumber were fastened to the inside of the foundation forms 2 feet on-center. A double layer of 1 1/2-inch polyisocyanurate foam board is attached to the battens with screws and plastic washers.

Double 2x4 walls and 14-inch-deep wood I-joist rafters minimize thermal bridging through the frame.

Note that the rafters' bottom plumb cuts are flush with the walls.

Precut studs, joists, and rafters saved labor and substantially reduced waste.

Even the rafter plumb cuts were made by the lumberyard.

Because of the 9 1/2-inch cavity created by the double 2x4 walls, the blown cellulose achieves an R-value of 31. The sides of the deep window wells are beveled 45 degrees to ensure that they let in plenty of light.

The second-floor band joists required blocks of 1-inch polystyrene, spray-foamed in place, to meet insulation goals.

Join the Discussion

Please read our Content Guidelines before posting

Close X