Crawl Space Vents

[JK_Byron]

Anyone seal off their crawl space vents? I'm looking to do mine as I picked up a pretty nice commercial grade dehumidifier. Seen some stuff on google, but I was thinking styrofoam block cut and then some expanding foam? Anyone have experience in this area for a good DYI material? Thanks.

 

[shawn]

XPS board cut to fit, Great Stuff to seal the gaps, visqueen on the floor, dehumidifier.

 

[moldman05]

I like the foil faced board. It resists rodents boring through. Be sure to seal all openings in foundation walls including around a/c ducts if you have a packaged unit outside. Use insulation board on access door along with a gasket and hardware to keep it closed tight