Q. Why Do I Need Spray Foam if I Do a Good Job Air-Sealing With Tyvek and Caulk?
A. Even a tight home with fiberglass will suffer a dramatic loss in performance and comfort because of convection currents that take place inside the porous fiberglass. A home with fiberglass in the walls or roof will permit convection currents and air movement inside the cavity, thereby creating a surface wall temperature that is either colder or hotter than the interior temperature of the home. As the temperature
differential between the inside and outside increases, the convection currents inside the fiberglass will speed up, literally transferring the heat into or out of the house. The result is a home that does not ‘feel’ quite right – either too cold or too hot. This is caused by radiant heat transfer taking place between the occupant and the surface of the wall or ceiling. Think of a cold winter day when you are sleeping next to a poorly insulated wall; the room may be warm, but the cold wall pulls the heat right out of your body. Simply from a comfort perspective, spray foam in the walls will yield outstanding results – particularly when the cavity is fully filled. (Click here for additional information)