Should I Insulate Floor Over Crawl Space

Should i insulate the floor over my dirt crawl space.

Should i insulate floor over crawl space.

There are two types of crawl spaces ventilated and unventilated and each requires its own form of insulation. The goal however is the same. When insulation is installed it is most commonly found between the floor joists to prevent the crawl space air from entering through the floors above. This type of crawl space also allows insulation with an r value of 19 installed in the floor joist if the crawl space and has a permanently installed dehumidifier.

However in a moist ventilated crawl space this insulation will eventually rot and become soaked with moisture this will cause it to fall off the ceiling and on to the floor. However the insulation needs to be treated with a fire retardant. An insulation contractor can calculate the ventilation your crawl space needs and will cut in new vents as required. This type of insulation allows for conditioned air to be introduced into the crawl space.

A crawl space under a house helps protect against certain pests but a crawl space with abundant moisture can invite problems including mold wood rot and vermin. People ask me all the time if insulation is necessary in the crawl space. Holes for electrical wiring and plumbing should be sealed with spray foam insulation. If you are thinking of insulating the floor over a dirt crawl space we recommend you think about the long term of what you will be doing with the crawl space if you plan to encapsulate the crawl space your insulation procedure may be different than if you are.

It will also help to stop that echo that can be heard when you walk on the floors suspended over a crawl space. The idea is to condition the crawl space much in the same way that you might condition other parts of your home. Rather than trying to cut off the crawl space from the conditioned upper floors you should bring the crawl space nearer to upper floors temperatures by leaving off the underfloor insulation and by sealing the crawl space against outside moisture and temperatures. Department of energy recommends r 11 3 insulation under floors in warm climates and an r 25 6 to 8 in cold climates.

Insulation of foundation wall and floors above many crawl spaces are built without any insulation in them. Fiberglass insulation batts or rolls are the most economical and easiest diy choice for insulating between the floor joist in a crawl space. Cold air that sweeps through a crawl space meanwhile can lead to cold floors inside the home whether or not the space is wet. Fiberglass insulation on the floor joists in a crawl space will help keep the floor above warm.

Without insulation heat and cool air are easily lost through the floor.