How to Cover a Crawl Space

The crawl space in your home is meant for workers to access utility equipment that is in your home such as electrical wires, plumbing and duct work. Unfortunately, many builders do not seal the crawl space to prevent moisture intrusion. When moisture enters the crawl space, vapors are released which can cause mold and mildew to form. With the crawl space not being sealed you will also find that air will circulate from within the crawl space to carry it all over the home. This can also cause heat and cool air to escape the home so your expenses for heating and cooling the home will be higher. The following information will show you how to properly cover your crawl space.

Step 1 - Clear the Crawl Space

Everything that is inside the crawl space should be removed from it, especially if there are pieces of wood or cardboard in there. This is because the dampness of the crawl space will cause these materials to grow mold and mildew. You will also want to remove any water that may have collected in the space. Standing water can breed insects and other potentially harmful bacteria. Always wear a protective mask when doing this. If there are visible signs of mold or mildew you can make your mold killer by mixing 1/3 cup of detergent with one liter of bleach and three liters of warm water. Place this mixture into a spray bottle and spray all areas of the crawl space with it.

Step 2 - Placing the Vapor Barrier

You will be laying the plastic sheet or vapor barrier twice. Take the sheets down to the crawl space and lay them over the dirt floor. Make sure you cover all of the area. As you spread the sheet out you should press on it so that you remove any trapped air. With this first layer placed you can now cut it as you need and start laying down a second layer on top of this one. As you place it also lay bricks on top of it to keep it in place. As you are moving along the plastic, the bricks will keep it in place so you do not have do the work all over again. Use the duct tape to seal the seams of the plastic sheeting. There should be overlap throughout the sheet which makes it easier to seal it. Once sealed; place a layer of gravel or sand on top of the plastic. This helps absorb escaping moisture as well as stopping drips from above.

Step 3 - Insulate the Foundation Walls

In order to keep moisture out you should cover the walls of the foundation with the insulation. This will stop the concrete from sweating; creating moisture. It is not necessary but you could add a layer of vapor barrier on top of the insulation.