I recently bought a house that has a crawlspace with some moisture issues due to leaking pipes. I've fixed all the leaks, removed the old insulation and damaged vapor barrier. Now, I'm planning to treat the wood with Boracare to prevent mold and install a new vapor barrier. However, I'm confused about how to handle the vapor barrier around the walls. My foundation has a mix of cinderblocks and wood, with one-third being a concrete slab floor and the rest being a dirt floor. Should I just put the vapor barrier down on the floor or does it need to go up the walls too? If it doesn't go on the walls, how do I secure it to the floor? Any advice would be appreciated!
2 Answers
I did something similar and covered the walls about 1 foot high with the vapor barrier. Make sure to tape it securely. You don't want it all the way up the wall because moisture can get trapped, so allowing it to fall back to the ground helps prevent rot. I also added foam block insulation to seal off any gaps and keep critters out. Since I did this, there's significantly less moisture, and the floor stays warmer now!
From my experience, cinderblocks are pretty porous and can let moisture through. I usually take the vapor barrier up to the top of the foundation wall and then insulate the rim joist with foam boards or spray foam. Just make sure to seal the vapor barrier to the insulation as well. Watching some YouTube videos by Crawlspace Ninjas is a good idea too; they provide various perspectives that might help you find a solution that suits your situation better.
That sounds like a great idea! I’ll check out more videos to get a better understanding before I dive in. I've seen some but still need specific answers.
So just tape it 1' around the wood and blocks? I think skipping the fiberglass insulation is a good plan since it doesn’t seem to work as well as people claim.