Is mold growing under an encapsulated crawlspace a concern?
On a project we are doing , the home owner is very reluctant to encapsulate the crawlspace because he believes that mold will grow on the ground side of the vapor barrier and the spores will end up migrating into the house. We both know that having a completely airtight ground barrier is impossible so slight infiltration is expected. Has anyone documented this problem occurring? He wants to close the vents, install a loose fitting vapor barrier, and a dehumidifier. The original builder(home built in 1976) put fiberglass bats perpendicular to the joists and then laid the sheathing on top of that. With that situation, I can’t use the argument about bats not staying put in the crawl. He believes that it has performed well so is reluctant to change.
We are also converting the old garage to living space with an floor elevated to that of the house. It will have about 14″ of space between the bottom of the joists and the existing slab. I see no reason to remove the slab though I doubt that there is a vapor barrier below. Would a coating of Drylock or similar waterproofing masonry paint and urethane perimeter caulk take care of any potential moisture movement?
GBA Detail Library
A collection of one thousand construction details organized by climate and house part