Unlike fiberglass, rigid foam insulation does not collapse or break under pressure. It forms an excellent air barrier to help you save more on energy usage. Unlike traditional insulations, it is resistant to moisture and will not be worn away by the weather.
Your basement is a large contributor to the home’s efficiency of energy, as well as your personal comfort.
All in all, even if you don't use your basement that often it's still worth investing in it. Consider improving the air sealing and also upgrading the insulation to squeeze every last drop out of its efficiency.
Air sealing is a way of stopping the disturbance of air from outside to come into your basement. That means that doors can't be too big or else you risk bringing in even colder air. Sealing the foundation is also key to running a comfortable space in your home because if it's not done, cold air can enter, and warm air escape.
Without knowing it for years, builders were unknowingly installing fiberglass in a section of the floor/ceiling joists that is between the ground and the basement.
Despite this, this insulation does not stop air from flowing from the basement to the envelope, which is supposed to have free-flowing air. The envelope is like a border between the inside of your house and the outside.
Proper insulation for the basement walls will keep the dampness and cold air out. Houses with an insulated floor below ground level are typically more comfortable and there is also protection from pipes, ducts, and other heating/cooling elements which could otherwise be damaged.
With this protection, you can avoid poor performance from your appliances and have lower energy costs.
Stiff foam can be insulated from either the inside or outside. It is usually easier to install it on the inside, though.
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