Attic Insulation - How to Make a House Energy Efficient

In this episode of the On the Job series, Larry Janesky, owner and founder of Dr. Energy Saver, walks us through the many ways they made a typical cape house more energy efficient.

This cape had poor attic insulation and serious air leakage, which increased the homeowner's energy bills and caused serious ice damming problems during the winter. As the snow melted on the roof, a ridge of ice forced trapped water to leak into the house. The water damage to the attic and living area raised health and mold concerns. The problem was so significant that during an especially heavy winter storm in the previous year, the homeowner had to climb on the roof and manually break the large ice ridges to keep water from pouring down his kitchen cabinets.

To fix this problem, Dr. Energy Saver completely air sealed the attic to keep heated air in the living space from leaking into the attic. The bathroom fans that were venting into the attic were fitted with ducts to vent to the outside, thus preventing all the air and moisture from leaking into the attic space.

Cape style homes like this one usually have a knee wall space. It is a small space created at the angle between the roof and the floor. A knee wall is usually a big source of energy waste. So the next step was to insulate and air seal the knee wall using a special type of rigid foam board insulation called SilverGlo™, which is lined with a radiant barrier to help conserve heat.

The last step was to insulate the attic, which was originally insulated with a thin layer of fiberglass batt insulation, which measures way below the R-60 value recommended by the U.S. Department of Energy for attics in that region. Besides having insufficient R-Value, fiberglass insulation does not stop air flow.

To insulate this attic, Dr. Energy Saver chose TruSoft™ cellulose insulation. Cellulose insulation is basically recycled newspaper that's treated with borax to prevent pest infestation and mold growth, and fire retardants which give the material an excellent fire safety rating. Cellulose insulation is denser than blown fiberglass and has a higher R-Value of 3.7 per inch. A layer of 17 inches was blown into the attic, with special attention to rafter bays and small cavities created by typical cape style architectural features.

This cape is now ready for winter. The homeowner has a more comfortable house, and his energy bills are much lower. To learn more about ways to save energy in your home, stay tuned for more episodes of Dr. Energy Saver's On The Job series, or call one of our certified energy conservation technicians for a home energy audit!