Crawl Space Fans: Do They Work?

 

Using crawl space fans to blow outside air in and control moisture in the crawl space sounds like something that makes a lot of sense. After all air is known to dry things, therefore by increasing the amount of air that gets into the crawl space, things will dry out better and faster. Right? 

 

Wrong!

 

What if I tell you that the air already coming from the outside is actually the reason why your crawl space won't dry?

 

Here's what happens:

 

Crawl spaces are naturally cooler than the outside. Usually 10 to 20 degrees. So let's say we have a nice day outside, with 80 degrees and an average 70% relative humidity. Your crawl space is about 60 degrees, which is cooler. When that air from outside comes in, it will cool down too. 

 

When that happens, the relative humidity in the air will increase about 2% for each degree the air is cooled. 

 

20 degrees cooler means 40% increase in humidity. 

 

40% added to that 70% that was already in the outside air will result in over 100% RH and since the air can't hold more that 100% moisture, can you guess what happens? 

 

It will give out some of that moisture and your crawl space will get more wet, as the water will condensate all over, causing your floor joists to grow mold and rot.

 

In fact, every time the relative humidity in the crawl space rises about 60%. mold is likely to develop. And with a vented crawl space that happens quite often, especially in warmer climates and in areas where the summers are humid and hot (like Dallas-Fort Worth). 

 

The best, and U.S. Department of Energy recommended way to treat a crawl space is to encapsulate it. That means, line the whole space with a vapor barrier, seal it to keep ground moisture and outside air from getting in, then run a dehumidifier to keep it dry and conditioned year round. 

 

This procedure. will not only solve crawl space moisture problems once and for all, protect your floor joists and hardwood from rot and buckling, but will also make your whole house an average of 18% more energy efficient, by cutting energy losses and eliminating problems such as cold floors and cold drafts from the crawl space during winter. 

 

Our CleanSpace crawl space encapsulation system was developed by Basement Systems, the company that pioneered the encapsulation technology, based on more than 20 years of experience in developing solutions for foundation moisture control.  The patented,  professionally  installed CleanSpace system remains the best solution for your crawl space and Olympic Restoration Systems is the Authorized CleanSpace Dealer in Dallas-Fort Worth and the surrounding areas. 

 

Contact us for a free crawl space repair estimate!