Basement Insulation

Basements are excellent areas to finish for extra bedroom and game room space. In fact, when you insulate your basement, then you can improve the insulating value of your house by 20 to 25 percent. Finishing a basement may require a degree of patience and special attention.

Insulate the Rim Joists (aka Bonds).

Current building codes in Michigan only require that bonds be insulated with R-13. We recommend that this be increased to R-19. The reason is that bonds cannot be covered with typical vapor barriers as they are flammable. Bonds are to be insulated with unfaced insulation or a flame-retardant vapor barrier. The best way to insulate the bonds is to use unfaced fiberglass that has a R-19 value or greater. In our region, R-19 is sufficient to keep moisture laden air from condensing inside the house.

Insulating Poured/Block Concrete Walls

Make sure that your basement is leak free. We recommend that if your house is newly built, wait a few months before finishing your basement to make sure the walls are fully cured before hiding potential problems within a wall system. Most settling of the house occurs during the first year, so we recommend that you wait.

When the basement is ready to insulate, there are a couple of options:

1) Fire-rated vinyl insulation. This insulation is expensive, but is the only option if you will not be furring out the basement walls. This insulation is attached to the concrete with plastic capped nails.

2) Wood Basement. Simply insulate as you would normally.

3) Preformed Concrete walls: These precast units are an excellent choice for basements. They provide the strength of a poured wall system and enable you to insulate them with standard fiberglass batts, blown cellulose or spray foam.

4) Owens Corning wall sytems: These attractive panel systems are easy to install and allow for access to the concrete wall system. If a leaky basement develops, this is an excellent system that allows for easy repair.

Questions We Have Been Asked About Basement Insulation:

What about using a polyethylene vapor barrier or stranded house wrap like Tyvek? We strongly recommend against this. Condensation will build up between the basement wall and vapor barrier. The moisture will settle along the bottom of the wall and create a dangerous black mold issue.