How To Seal Crawl Space Vents
To make that happen we seal off crawlspace vents using foam board and spray foam.
How to seal crawl space vents. Add a thermal barrier to the crawlspace walls. If you decide to not seal off crawl space vents year round the simplest way to close your crawlspace vents for the winter is to plug them from the outside with foam blocks made specifically for crawlspaces. The most cost effective method is to insulate the vent cavity with 2 foam board.
That s because you ve done nothing to dry out your crawl space. Because you are trying to completely dry the crawl space out you ll need to start by eliminating groundwater seepage. After all if you have open crawl space vents it s essentially just another way for pests to enter into your crawl space.
There are two things you must do before you ever seal the crawl space vents. Crawl space vents can also add to this problem. The same goes for sealing the vents if all you do is seal off your crawl space vents you effectively seal the condensation humidity and mold inside your crawl space.
There are many different methods to seal the crawlspace vents. We also attach foam board to the crawlspace door. The foam board is cut to fit the vent cavity and is sealed around the edges with spray foam to ensure there are no air leaks around the edges of the seal.
To further prevent outdoor air from entering your crawlspace we attach foam insulation to all crawlspace walls.