Wednesday, September 1, 2010
Crawlspace Condensation - Sweating Ducts
With record summer heat and humidity, we have been receiving an enormous amount of calls from homeowners about their sweating crawl spaces. Most homeowners are unaware of what is causing their ducts, pipes, insulation, and sometimes wood structure to sweat in their crawl space. Surprisingly, the very thing that a homeowner thinks is drying their crawlspace (ie. vents) is actually the culprit behind their crawl space condensating.
Foundation Vents are causing condensation!
In the summer months when temperatures are in the 80's and 90's, the outside air is very humid. The crawlspace is consistently 55 - 60 degrees and cooler year round because of the earth's soil. When this hot, humid air is vented into a cooler environment, the coldest surfaces in the crawlspace will begin to condensate. It's the same concept as taking a cold glass of coke outside on a hot summer day. The surface of the glass is going to start sweating. So when venting a crawlspace on a summer day, there is going to be condensation on the crawl space walls, crawlspace floor (dirt or concrete), air ducts (especially when the AC is on), and cold water pipes. These surfaces are the coldest. On very hot days, floor joists, beams, sill plates, and insulation condensate as well.
Foundation Vents are causing condensation and higher heating bills!!
When your air conditioning travels through your duct work in a vented crawlspace in the summer, the cooler air in the ducts is competing against the outside humid air being brought into the crawl space. The AC unit will have to work twice as hard to compete against this outside air. Also, this humid summer air puts a latent load on the HVAC system because the AC system has to work harder to dehumidify this damp air. For more info as to why see my post "Foundation Vents are causing higher energy bills".
Foundation Vents are causing condensation, higher heating bills, and MOLD growth!!!
Another common problem with ventilation and condensation in the summer is the propagation of mold spores. Mold needs between 65% to 70% relative humidity in the air to remain active and produce spores. Outside summer air can reach 80 to 90 percent relative humidity on any given day. This humid air by itself can lead to an environment conducive to mold growth, especially when this air is reaching the dew point on cooler surfaces. Also, many homeowners spread mulch around their foundations and vents. What they do not realize is that mulch contains high levels of mold spores and that these spores are being introduced into a perfect environment for mold growth in the crawl space.
Crawlspace Condensation SOLUTION!
Since foundation vents are causing condensation, higher energy bills, and fungus growth, they should be closed and the crawl space sealed with our AmeriBrite crawl space encapsulation system. It is not recommended to close off the vents permanently without first encapsulating
If you live in Indiana, Ohio, Kentucky, or Illinois, and are tired of dealing with crawl space
condensation and interested in encapsulating your crawlspace, give us a call 1-877-409-2837 or
SIGN UP ONLINE for a FREE ESTIMATE.
Thanks for reading the rambling thoughts of a crawlspace inspector,
Larry Ralph Jr., Becky, Daniel, and Aaron