Does Insulating Basement Walls Help Heating Costs?

Basements are often difficult rooms to insulate after construction.

Insulating your basement can reduce your energy costs, saving you money each month. However, the success of basement insulation largely depends on its correct installation. Insulation can be placed on interior walls or on exterior basement walls. Homeowners who want to insulate their basement must consider the cost, moisture control and installation methods.

Identification

According to the United States Department Of Energy, the most cost-effective way to insulate basements in existing homes is by installing insulation on interior walls. There are a variety of products that can be used to insulate interior basement walls that are less expensive to install than exterior insulation. However, there are some disadvantages to interior insulation. If the basement has poor drainage, the insulation may become wet if moisture comes through the basement wall, eventually causing mold growth. Interior insulation also reduces usable space by 2 or 3 inches. Exterior insulation has its advantages. Placing insulation on exterior basement walls reduces condensation, conserves room space and protects the damp-proof coating on your home.

Types

Foam board insulation is commonly used to insulate basement walls. This type of insulation adds strength to the structure of your home and reduces energy use. Molded, expanded polystyrene foam board is also known as bead board. A vapor retardant is necessary with foam board insulation if moisture seeps through the basement walls. Sprayed-on foam insulation is a good option for existing basements. Some types of spray foam insulation include polyurethane, phenolic and cementitious, all of which are liquid products. Spray foam insulation must be installed by a certified insulation contractor.

Benefits

Insulating your basement can reduce energy usage, bringing the cost of your electric bill down each month. How much your energy bill is reduced depends on the climate where you live, your lifestyle, what type of heating and cooling system you have and the current cost of fuel. While homeowners can install insulation themselves, achieving the maximum benefits from insulation requires that it be installed correctly. The United States Department Of Energy recommends that homeowners have their basement insulation installed by a licensed professional to get the most benefit from their insulation.

Considerations

When insulating the basement, homeowners must also consider adding the right moisture control. Basements are humid and damp, a perfect breeding ground for mold and mildew. If the basement has moisture seepage, then the insulation may become wet, and mold may grow. Vapor barriers are applied in a paint form or as a membrane covering. Air sealing should also be done inside basements for maximum energy savings. Sealing all cracks and openings in your basement will keep air from coming into your home and reduce your heating costs. Air sealing alone will not reduce heating costs significantly; you must add insulation to maximize the effect.

References

• U.S. Department Of Energy: Basement Insulation
• U.S. Department Of Energy: Sprayed Foam And Foamed In Place Insulation
• U.S. Department Of Energy: Foam Board Insulation
• U.S Department Of Energy: Air Sealing