Will Using a Crawl Space Vent Cover Prevent Flooding?

It was once believed that vents would help crawl spaces with air circulation and humidity. Unfortunately, we now know that this isn’t the case, and that crawl space vents allow water in as well as hot air from the outside. With this new information, homeowners are now purchasing crawl space vent covers to seal off the opening and improve the health of their foundation. While this is an excellent first step, it isn’t enough to solve all your flooding and humidity problems. You’ll need more than just a vent cover if you wish to lower your energy bills and keep the humidity at an all-time low.

Water vapor can still seep through the concrete walls and raise the dampness levels. At a certain point, when the temperature of the crawl space reaches its dew point, the moisture in the air turns into water droplets along the surface of your concrete, wood, pipes and HVAC ductwork. If there are enough droplets, they will pool together and form a puddle inside your crawl space. This becomes dangerous during the winter because of the freeze-thaw cycle. All the moisture in your crawl space will freeze, expand, and displace the soil, tear up the concrete, and deteriorate wooden posts.

If the humidity is allowed to persist, there will be foundation damage so significant that water will seep through despite the existence of the vent cover. Besides a vent cover, your crawl space needs a vapor barrier, a dehumidifier, and a sump pump. It may seem like much, but you have to remember that crawl spaces are built partially underground. They are the part of your home that gets exposed to moisture the most, so you need to cover all your bases to truly protect it.