InstantForum.NET v4.1.4Therma-Stor Forumhttp://www.thermastor.com/forum/web@thermastor.comFri, 04 Jul 2008 06:31:59 GMT20http://www.thermastor.com/forum/Topic780-11-1.aspxI assume that along with plastic on the earth, the outside vents are closed. With a wood floor between the crawlspace and the main floor, moisture migrates between the crawlspace and the home. Therefore, maintaining 50%RH on the main floor usually keep the crawl dry enough to avoid mold. </P><P>I suggest a dehumidifier on the main floor and monitor the crawl %RH. Should not exceed 60%RH. Wal-Mart has a remote %RH meter for $30-$40 with high/low memory. Dehumidification is not required during cold weather because the outside dew points are very low(&lt;55^F). Any of the Santa Fe will do the job. Using a Santa Fe Advance is the best value. Also a duct kit can be added in the Advance if the crawl requires some ducted dry to be kept dry. Keep us posted. Ken Wed, 03 Jan 2007 08:03:12 GMTKen