Insulation - Making Knee Wall Spaces Energy Efficient

On this episode of Dr. Energy Savers' On the Job video series, owner and founder Larry Janesky, discusses the significance of insulating and air sealing the knee wall space and demonstrates the proper methods within this home.

Knee wall spaces are small spaces commonly found in finished attics beneath the roof rafters. These rooms are most often found in attics with either cathedral or sloped ceilings behind a short wall and come with or without a small door to access the area. Dr. Energy Saver air seals and insulates this knee wall space to help improve the overall comfort and efficiency of this home.

Overview of Knee Wall Spaces

Overview of Knee Wall Spaces

Typically these spaces are treated as if they were outside the thermal boundary of the house. They are not insulated as you would normally insulate an attic, and the small wall that separates it from the living area isn't insulated either.

The roof above the knee wall can reach scorching temperatures during the summer, and get freezing cold during the winter. In addition, soffit vents used to vent the roof allow dirty, unconditioned air from the outside to flow inside the home.

The unconditioned air will then leak into the conditioned area, transferring its extreme temperatures to the whole house through the walls and cavities.

All of this air leakage and heat transfer makes your home much harder to cool and heat, increasing your energy bills. That is the reason why in homes with knee wall spaces, Dr. Energy Saver considers knee wall insulation an energy efficient priority along with attic and foundation insulation.

How to Treat Un-Insulated Knee Wall Spaces

How to Treat Un-Insulated Knee Wall Spaces

In this particular case, the knee wall was insulated with SilverGlo™ , a product that is exclusively available through the Dr. Energy Saver network. SilverGlo is a high R-Value, graphite-infused insulation foam board, lined with radiant foil that reflects the sun's heat away from the home during the summer, and maintains the heat during the winter.

The space was then completely air sealed to stop air leakages, and is now included in the building's envelope. Without the extreme temperatures and the air leakages, the space is now clean and suitable for storage. The adjacent rooms are more comfortable and energy efficient.

The Benefits of Insulating the Knee Wall Space

The Benefits of Insulating the Knee Wall Space

Once the knee-wall space is air-sealed and insulated properly, this space is brought into the thermal boundary of the home. Finished rooms with knee-wall spaces adjacent to them will no longer feel the effects of hot and cold air penetrating the room.

Once our job is done the knee wall space could now be used as storage, keeping your possessions out of the cold harm of severe temperatures. An insulated and air-sealed knee wall space will make a huge difference in the overall comfort and efficiency of the home, especially multi-story homes. This space will now block heat from infiltrating the home and keep conditioned air inside the home, putting less dependency on your heating and cooling systems and ultimately, saving more money.

Dr. Energy Saver Takes Care of Your Knee Wall Space

Dr. Energy Saver Can Air Seal and Insulate Your Knee Wall Space

If your home has untreated, uninsulated knee walls or any architectural features that might be causing energy waste, contact your local Dr. Energy Saver today, for a free estimate and evaluation.

We specialize in making homes more comfortable and more affordable to own!

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