Definition for word: Crawl Space

A shallow space below the living quarters of a house, normally enclosed by the foundation wall. Most crawl spaces have dirt floors.

Referrence from

A crawl space (as the name suggests) is a type of basement in which one cannot stand up — the height may be as little as a foot, and the surface is often soil. They offer a convenient access to pipes, substructures and a variety of other areas that may be difficult or expensive to access otherwise. While a crawlspace cannot be used as living space, it can be used as storage, often for infrequently used items. Care must be taken in doing so, however, as water from the damp earth, humidity entering from crawlspace vents, and moisture seeping through porous concrete will create a perfect environment for mold, mildew to form on any surface in the crawlspace, especially cardboard boxes, wood floors and surfaces, drywall and some types of insulation. Health and safety issues must be considered when installing a crawl space. As air warms in a home, it rises and leaves through the upper regions of the house, much in the same way that air moves through a chimney. This phenomenon, called the "stack effect," causes the home to suck air up from the crawlspace into the main area of the home. Mold spores and fecal material from dust mites in the crawlspace come up with the air, agitating breathing problems such as asthma and creating a variety of health-related problems.

These can be placed directly on the dirt, but it is more desirable to finish with a plastic vapor barrier that will not support mold growth or allow humidity from the earth into the basement. This helps to insulate the crawlspace and discourages the habitation of insects and vermin by breaking the ecological chain by which the insects feed off the mold and vermin feed on the insects as well as creating a physical inorganic barrier that deters their entrance into the space. Almost unheard of in the 1990s, these barriers have become increasingly popular in recent years.

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