Energy savings is on most peoples’ minds these days especially the homeowners who live in northern areas. The cost of heat and making sure the home prevents heat form escaping is one of the main topics of discussion at the home supplies stores. For many of those who have older homes with basements much of the area is already in finished condition but there were areas of the basement walls that were left with bare walls as storage spaces. New homes are usually built with the insulation going down below the frost line and stopping abruptly because the building code states that this insulation only has to go down that far.

Basement Wall Thermodynamics

Most basement walls are constructed with concrete or concrete blocks which is a mixed blessing. For strength concrete is peerless in this use and concrete keeps getting harder over time. IN addition concrete is a great heat storage material just like clay brick. You can test this by feeling a concrete wall on a summer’s evening after its exposure to the sun for a few hours. Heat will be radiating from it as the heat in the concrete is drawn out by the cooler evening.

In the basement some people will attest to the fact that warm basement walls mean a warm home. This is true because if the basement walls have heat then the upper floor must be warm. However, depending on the temperature of the soil, which stays around 40 degrees Fahrenheit below the frost line, the wall is cool on the outside. And since heat travels to cold it must take twice the energy to keep the inside wall warm as it does to heat the basement. In other words the concrete is a conduit for heat escaping. This is why it is essential to insulate the walls either from inside or exterior.

Basement Wall Integrity

Concrete basement walls can be affected by the movement of the earth, or from fluctuations from the curing process, and crack in places. As well, the corner seams and the joints where the wall meets the footing may leak over time because water has been drawn into minute fissures by ***. This is a problem for insulating because moisture trapped between the walls and the interior vapor barrier can produce mold. This happens in finished basements where the walls have not been allowed to cure before being drywalled.

For a bare concrete walls with moisture lines or pudding on the floor it is best to call in a professional to have this problem fixed. For the money invested it will ensure that your new wall will be dry.

Exterior Insulating

By putting a foam insulation sheathing around the exterior of the basement from footing to floor plate you will be keeping all that expensive heat inside and stored in the concrete until it is needed. As it requires excavating it is the most expensive method but you can multi-task by replacing the weeping tile system for better drainage and reseal the exterior walls. Once the walls are powerwashed and dried interlocking 4 X 8 foot foam sheets are installed with a special glue and then a waterproof membrane is put over the foam from below the footing up to above ground level. The ground water will slid down this coating and directed away naturally or it will seep down into the weeping tile system and into the sewer. The inside walls can then be strapped with 1” X 3” furring strips attached to the concrete with a Hilti gun or impact hammer. Then the paneling be installed over this.

Interior Insulating

Insulating on the inside basement walls is not only cheaper it is a great do-it-yourself project even by a novice.

Fiberglass Batt: Since most basements have eight-foot ceilings, standard 2” X 4” wooden frames with 16” centers are easily built on the flat concrete floor and raised up to fasten on the ceiling and floor. Fiberglass insulation fits snuggly between the studs and this is covered with vapor seal before covered with Gypsum board

Rigid Foam: There are interlocking rigid foam insulation panels that can be glued to the wall. These also have vertical grooves at 16” centers to accept strapping and so the project can go very quickly. These rigid panels can give you r-4 per inch so three inches will give a warm basement. Other, thinner foam panels have a finished surface and can deliver a similar performance.

Spray-On Foam: Nothing seals the home better than spray foam insulation. The product expands as it cures getting into every little spot that could leak from the outside. The best is close-cell because it will not break down over time like the softer, open-cell does. This is especially crucial if the spray is not being covered but just sprayed on the bare concrete to add insulation and sealing value.

Although basement insulating can be a do-it-yourself project it is best to get a professional basement expert out to check the concrete before covering it. For more information on concrete sealing contractors or complete basement remodeling experts consult our Contractors Directory. You can also post your project online at HandyAmerican.com and have a professional contact you directly.