Do I need crawlspace encapsulation for high humidity?
Contractors almost always recommend full encapsulation when crawlspace humidity causes condensation and damage, but standard vapor barriers are often no match for summer moisture. Homeowners are left trying to figure out if there are simpler alternatives to expensive encapsulation to protect their ductwork and floors.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
- 1Closing or sealing crawlspace vents during the high humidity summer
- 2Installing a crawlspace dehumidifier
- 3Testing humidity by blocking vents temporarily with rigid foam and renting a dehumidifier for a week
- 4changing fan setting from ON to auto
- 5inspecting areas around the house for air infiltration
- 6checking for leaks with a thermal imager
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“We have an American Standard unit and are dealing with humidity issues in our 1941 home that has caused a portion of plaster ceiling to drop to the ground, and tenting in the hardwood floors.”source ↗
“Had a few companies come out because our ductwork and AC system had condensation from high humidity levels in the crawlspace.”source ↗
“Both companies recommended full encapsulation and I’m just curious if there’s ANY other option.”source ↗
“the vapor barrier the builder put down is in good shape, but I guess with the humidity it’s just no match.”source ↗
Where this came up
People with this problem also raised
- 7How to stop mold and high humidity ruining a basement
- 17Why is my AC not lowering indoor humidity?
- 4Why is there condensation and damp spots on walls only on laundry days?
- 12Why is my AC air handler wet and smelly?
- 3Why is just one upstairs room so hot in the summer?
- 6Why are my metal floor vents sweating and growing mold?