Air Sealing and Insulation for Maximum Efficiency

Homeowner and carpenter Jeff Wilson hopes to save 50 percent to 90 percent on energy costs through his Deep Energy Retrofit (DER) project. To achieve this goal, Jeff must air seal his 70-year-old home and ensure the new garage/addition envelope is tight. He used two air sealing methods: one in retrofitting the original home and another involving new construction techniques for the garage/addition.

Using the original painted redwood siding as a foundation for new insulation, Jeff began creating a curtain wall by nailing 2x3 framing to the exterior.

Jeff and the crew worked on the original siding while building the new garage/addition. Here you can see 2x3 framing installed on the original siding and the frame of the addition, which will be insulated from the interior.

The original house was insulated from the exterior. About 2 1/2 inches of Foam-It Green spray foam insulation was applied between the 2x3s.

The spray foam will reinforce cellulose insulation that was blown into the walls of the original home five years ago. On top of the foam, sheathing was applied. This surface was covered with house wrap before SmartSide ready-to-paint engineered wood siding was installed.