How to Insulate a Stone Foundation

Many homeowners prefer to a have stone foundation for several reasons. It is the most common structural foundation of earlier houses or buildings and therefore the materials used in making a stone foundation are easy to find and order. Second, stone foundations are more durable than any other material. They are tougher than alternative materials. Another thing is that is when it comes to maintenance; they are less expensive to maintain resulting in fewer log term expenses. However, stone foundations tend to get cold and damp resulting to several problems such as mildew and musty smells. Foundations made of stone also cause significant amount of heat loss in the house. For this reason, insulation of stone foundation is necessary.

There are actually 3 types of insulation: polyurethane spray, rigid plastic board insulation and blanket insulation. The spray type of foundation would be the best option if your stone foundation is uneven and is having some moisture problems. However, it should only be applied by the professionals. Rigid plastic board insulation is probably the strongest but is usually more expensive. Whatever type of insulation you choose, make sure to estimate the total cost by checking with your local building supply dealer.

Step 1 - Assess the Situation

Before you begin, it is vital that you consider a number of factors which can affect how you insulate. Some of these factors include the type and condition of the wall, interior structures of the house that may impede the work, structural cracks or bulges, moisture problems, and finishing details. You must also consider if your area has problems with frost heave brought about by expansive clay soil. It is also advisable to consult a local builder before applying insulation to your stone foundation.

Step 2 - Inspect the Walls

Check the walls you will insulate for moisture problems. Installing insulation will be easy if you follow correct procedures despite occasional dampness on the basement. However, if water leakage is a frequent occurrence, make sure to repair the root cause of the problem first before installing insulation. Use a polyethylene moisture barrier to cover the basement walls. This will also serve as a strong protection for the insulation.

Step 3 - Put a Wood Frame Wall in the Basement

There are two ways of framing the wall. You may use a 2 x 4 inch lumber when installing the new wall flush to the old wall or use the same size of lumber which was built out from the wall itself. It is important to use dry lumber. If you are unsure about the lumber to use for framing, let it dry for about two weeks before installing it. Make sure to place the studs accurately with enough spacing in order to install the finish easily as well.

Step 4 - Install the Insulation

There should be two layers of insulation to install. A horizontal layer between the walls and the studs should be installed first. Make sure to install it tightly against the wall. Then, the vertical insulation which is the second layer should be installed accurately between the studs. Make sure there are no air spaces between the studs and the wall.

Step 5 - Install the Finishing

The finishing is usually composed of a vapor and polyethylene air barrier. These are placed over the insulation and the studs. Make sure that all the edges and penetrations are well sealed. Next, nail the surface of the finishing tightly against the insulation. Each joist ends should be air sealed to keep your stone foundation warm and dry.