How to Cover the Crawl Space in the Basement

Remove all objects from the crawl space. If there is any standing water, use a dehumidifier or shop vac if necessary. Remove any visible mold found in the crawl space as well. Use respirator masks when doing these activities. To make a mold solution, mix a third cup of laundry detergent, one liter of chlorine bleach and three liters of warm water.

Lay out the plastic along the ground on the crawl space. You may want to consider completing one section at a time before moving on to the next section to avoid having to crawl over the same space twice: once to lay out the vapor barrier, twice to seal it.

Place heavy objects, such as weights or multiple amounts of breaks, on the plastic so that you can lay it out and have it stay in place while you are sealing it. If you are having to crawl over the plastic while laying out and sealing other sections, there is a chance that by crawling over it, you will mess it up. Weighing it down helps to prevent this from happening. Sand or gravel is another option for weighing down the plastic.These have the added benefit of absorbing any other moistures that could drip down onto the plastic.

Tape and seal the seams between different sheets of plastic. When you lay out the plastic, there should be some overlap, which will make the taping very easy.

Cover the foundation walls with moisture-proof insulation. This helps to prevent rising moisture from the concrete from getting into the crawl space. If you use Thermax brand, you will not have to provide drywall cover for a fire barrier.