Crawl spaces are typically found in the attic or in the basement and, as their name suggests, they’re a pretty tight fit; repairmen use them to get to your plumbing or electrical wiring. Crawl spaces are guilty of losing both heat and cold, however, and making heating and cooling bills much larger than they need to be, and causing your home’s systems work harder than they should. A crawl space can also retain moisture, resulting in mold which can cause health problems.  And, since there is nothing beneath the floor to absorb the sound, your floors can become noisy.  The importance of crawl space insulation should be clear to you once you consider all this.

Your installation process for you crawl space insulation is dependent upon whether or not your spaces are ventilated. Usually, building codes demand that crawl spaces are ventilated in order to prevent moisture from building up inside. Many building professionals believe however, that a crawl space should be unventilated or have the vents closed once construction is complete and the space has time to dry completely. The reason for this is that in the winter, ventilation makes crawl spaces difficult to heat, and in summer warm, moist air brought in from outside by the vents does not dehumidify the crawl space and in fact, can even increase moisture.  It’s much easier to install insulation in unventilated crawl spaces.

First, you need to figure out who’s going to install the insulation: you can get professional workers to do it, but you might feel that you can do it yourself. It’s important to be as safe as possible if you want to tackle this yourself. Among the tools you should use, include a long sleeved shirt, gloves, and eye protection. The insulation material is obviously important: Batt insulation is the cheapest, its R-value at 20 for unventilated spaces and 10 if you’ve got vents. A material’s R-value is a measure of how effective it insulates; the higher it is, the better.

To avoid drafts, seal up any gaps, spaces or openings before you install the insulation in your crawl space. You can also seal up any external entry into the crawl space and create an entry from inside the house instead.  Remember that keeping control of your moisture levels is important. Apply a layer of vapor barrier on the floor to prevent soil moisture from rising into the crawl space.


Unventilated crawl spaces get a bit of a break: the foundation walls are all you need to install the insulation in. If your crawl space is ventilated, then you will probably need to get some insulation in spaces under the floor. Any pipes in the crawl space need attention, too; wrap all pipes in a layer of insulation to keep them from leaking heat and from freezing.

Applying crawl space insulation may be one of the most important improvements you can make to your house.  If done properly, aside from saving on energy costs, it can also make your home more comfortable.