Many homes built on crawl space foundations
in the Southeastern United States suffer from poor moisture
management. Some of the common symptoms of a crawl space moisture
Mold or moisture damage in the crawl space or living area
Musty odors in the living area
Condensation ("sweating") on air conditioning ductwork or equipment
Condensation on insulation, water pipes or truss plates in the crawl space
Buckled hardwood floors
High humidity in the living area
Rot in wooden framing members
These symptoms are most often noticed in the humid spring and summer seasons but can occur at any time of the year. Often, the heating and air conditioning contractor is the first person the residents call to deal with the problem. Typically though, the problem is not due to a failure of the air conditioning system; it results from poor moisture control in the crawl space.
For many decades, building codes and conventional wisdom have prescribed ventilation with outside air as the primary method of moisture control in crawl spaces. In the humid Southeast, however, ventilation with outside air only makes moisture problems worse. Recent research by Advanced Energy and others indicates that a new type of crawl space system, with NO vents to the outside, can provide greatly improved moisture control and significant energy savings when properly installed.
This page lists materials and information generated by Advanced Energy research projects, diagnostic investigations and collaboration with a variety of professional installers and consultants across the country. We hope this information can help you to improve your existing crawl space or to design and install a properly-closed new crawl space.
Design and implementation recommendations for closed crawl spaces
Four sample closed crawl space designs and a sample construction sequence
An overview of NC residential code requirements and issues
Recommendations for improving existing wall-vented crawl spaces
A summary of Advanced Energy's crawl space research results
Answers to frequently asked questions about mold in crawl spaces
You may purchase a wire-bound copy of the introductory reference, along with laminated copies of the quick reference sheets, for $45 by clicking here. You may also send the pdf versions available here for download to your local printer for duplication, as they are of sufficient resolution for high quality reproduction.
North Carolina Residential Building Code
The NC Building Code Council adopted new code language in September 2004 for both wall-vented and closed crawl spaces. The new language was approved by the legislative rules review process in November 2004. Click the links below for more detail:
Detailed reports of research goals, methods, results and conclusions that have been created per the contract requirements of Advanced Energy crawl space research sponsors and funders.