Venting Options for Damp Crawlspace

JoeB asks,

We have a 28″ high, 2,200 square feet crawl space with a dirt floor covered by plastic sheeting and walls of exposed concrete block and perimeter beam walls. the walls have 12 vents each one being 4″ x 10″ scattered around the perimeter. We live in East Texas where it is humid much of the year. During the summer the relative humidity in the crawl space is often 90% day and night. The relative humidity in the crawl space tracks the average humidity of the outside air, that is, when the humidity outside is, on the average, high the humidity in the crawl space will also be steadily be high and vice versa. It seems to me using an exhaust fan to pull outside air in will just make the situation worse.

I heard Tom mention on one of your radio programs that Wave Home Solutions had a product which pulled a small amount of conditioned air from the upstairs down into the crawl space and at the same time expelled an equal amount of crawl space air to the outside. Since I heard Tom say that I have done some research and found another company that offers a similar product, EZ Breathe.

Both companies charge between $1500 to $2000 uninstalled. I have also read reviews that are mixed some saying it works and some say it doesn’t. This is a lot of money to spend on two fans and some ducting especially if it may not perform. Do you have an opinion on these systems and, hopefully, some experience with them?

Our Answer

I have no experience installing Wave Home Solutions or EZ Breath systems in my own home, because I never fully believed they would work as advertised. Initially they seemed promising but I grew concerned that they might only work in limited circumstances, such as where the humidity was less prevalent than in your area. Time has shown that there are many, many unsatisfied customers so it’s pretty clear they are not the end-all solution they are often portrayed to be.

In your case I’d do the following:

Use a vapor barrier on the floor and walls;

Improve the drainage at the foundation perimeter to keep as much water away from the home as possible.

Use an efficient, properly size dehumidifier, like those from SantaFe. Here’s a dehumidifier video I did on when I put one in my own home that’s been working great.