How To – Is A Sub-Floor Necessary To Install Carpet In Your Basement?

Many people finish their basements to add a playroom for the kids a recreation room for the family or even another bedroom for family and guests.

When converting your basement to a finished living space there are many considerations including whether to put insulation in the walls,  whether to drywall or add a drop ceiling and what type of flooring will make that drab underground area feel comfortable to live in.

If your home has a concrete basement floor you most likely can install any type of flooring you want including carpet, wood or tile but the problem some people run into is a high moisture content in the concrete which can cause problems if precautions are not taken before the install.

In the late 1980’s early 1990’s there was a fad where contractors suggested installing a vapor barrier and then 2×4 framing and a sub-floor.  Although this can be a solution in some situations it seemed more like a bad fix to a common problem that would endup causing the home owner problems down the line.

If your basement walls are made of stone and mortar and the age of your home pre-dates the use of sump pumps that are now standard in almost every area then you could have a moisture problem that can interfere with your refinishing project. Instead of putting a bandaid on the problem by installing a sub-floor you should look into installing a sump pump system which will extend the life of your home and reduce the amount of moisture in your basement.

If you have moderate moisture problems in your basemen then the use of dehumidifiers can reduce moisture but this can be expensive over time.

Preparing Your Basement Floor For Carpet

To install carpet in your basement you will need to apply a poly plastic moisture barrier under the carpet and pad and many contractors may suggest that you first apply a concrete paint that is formulated to block moisture.

I would suggest that you use moisture block paint for carpet or wood floor but it is not necessary for ceramic tile.

Some contractors will suggest that you install the carpet by gluing it to the concrete and not using a carpet pad under it. This is a cheap solution and can be used in high moisture situations but you are not always limited to this type of install.

If you can use a carpet pad you want to make sure  it is a closed cell rubber padding and not a open cell product that can hold moisture. Natural fiber padding is never a good idea in a basement.

Attaching the carpet is performed in the same way as in the rest of your home but you will need to use concrete tack strips that have special nails to bite into the concrete.

You also want to make sure the carpet installer uses a stretcher not just knee kickers to install the carpet. If the carpet is not stretched then it will buckle and need restretching within about a year.

Final Note

Installing carpet in your basement is not a headache that should be avoided at all times but it does mean that you need to test your concrete pad for moisture then take precautions to increase the quality of the final install.

If you have heavy moisture in your basement then you are likely to have additional problems such as mold growing in your fabrics used in your furniture and problems with any paper storage or art work you may include.

Eliminating moisture may mean installing a sump system and this can be expensive and difficult in older homes with stone and mortar foundations because hand digging around the outside of the home will be necessary.

Finally when a contractor suggests that you install a sub-floor in your basement it is an indicator of their inability to offer you a best service or a serious moisture problem that needs a better solution.