YEAR-LONG INDEPENDENT INVESTIGATION
by Peter Carpenter

A Smartvent crawl space ventilator was installed in a crawl space, and every 4 hours from 9/22/03 to 10/24/04 crawl space temperature and relative humidity (RH) measurements were collected.

The results are remarkable. Crawl space humidity averaged 46.4%. Crawl space temperature averaged 58.4°. Out of 2289 observations made, 14 (.61%) were above 70% RH, 264 (11.5%) above 60%.

Maximum and minimum humidity recorded was 74%RH and 24% RH respectively. Maximum and minimum temperatures recorded were 75° and 40°. Prior to installation of the Smartvent the crawl space humidity was noted to be about 70% on the low end, 99% on the high end.

Because of air quality issues, most experts have concluded a crawl space must be ventilated to the outside. There may be radon issues. Under the vapor barrier it is always 100% RH, so molds, spores, and bacteria thrive. Plus, a crawl space is never cleaned so there will be insect debris & droppings. Vapors from the above will migrate into the home.

One might seal a crawl space pretty well, but it is not possible to seal a crawl space sufficiently to prevent outside airborne water vapor from migrating inside. So, the patented Smartvent technology looks for very small (or large weather variances), compares inside and outside airborne water vapor pressure, moves a lot of air whenever it?s favorable to ventilate, doesn?t when not favorable.

The object is, over a period of time, to slowly ratchet down the wood moisture content to well below mold threshold.

The Smartvent is a cost effective solution to controlling moisture in every crawl space, offering low installed cost and an operating cost of less than $10 per year.


Data for this article was collected by:
Professional Investigative Engineers (PIE)
Edward L. Fronapfel, M.S., P.E.

The information in this investigation is in line with our own moisture study done in 1999. That study is posted on the web at http://www.smartvent.net/docs/crawlspacestudy.pdf

Peter Carpenter
Smartvent, Inc.
3255 Cimarron Drive
Conway, Arkansas 72032
501 329 4915
http://www.smartvent.net