...Last night I was wiring. Along the front wall of my house (basement wall), I pulled out a row of insulation. My house is built like this: Foundation ----> vapor barrior (on the backside of stud wall)------> Inusulation -----> vapor barrior on the outside of stud wall. So basically I have vapor barrior sandwhiching the studwall. When I took the insulation out, the inside of the vapor barrior and the back of the insulation were sort of wet. Not drenched, but there were drops of water on the vapor barrior. I could run my hand over it and get a wet hand. This is on the INSIDE of the vapor barrior. The foundation wall doesn't look at all wet. I was able to look at the top of the wall and it wasn't at all wet. Any idea what might be happening? Could it be sweating, or do I have a water problem. There is no moisture on the outside of the either sheets of barrior...
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tsherv, you will probably get all kinds of different opinons but from my experience it appears you have one too many vapor barriers.The only barrier you should have is the one between the foundation and studs.What is happening is that moisture is getting trapped between the two plastic sheets.
Moisture is just about always going to seep into a basement wall. It would seem that your issue is almost one of humidity through the masonry, which is fairly common.
A key issue not addressed in your posts is the condition of the studs and especially the soleplate they are attatched to. If the moisture is starting to degrade the structural integrity of the wall, immediate action is required unless you're up to tearing it all out and re-doing it. If those pieces are OK, this issue becomes an annoyance rather than a real problem.
If this is an annoyance, one option to try is to see if you can vent the moisture somewhere. It may seem counterproductive, but something that would allow the moisture to escape may be something worth trying, and if that means removing some (or all) of the most accessable vapor barrier, that might be worth it. Wet insulation is useless anyways.
If your soleplate or studs are degraded, you have little option but to at some point tear them out and replace them. I've heard that reinstalling everything with a one inch open space between the studs/insulation and the wall allows things to breathe a bit. I'm finishing out a basement now, and using that method, but it'll be a while before I learn how effective that is.
Good luck.
Greg
It is much more than an annoyance. Allowing the condition to continue is providing a home for mold, one of the building industries worst problems since the seventies, when homes began to be tightened up.
You should NEVER have two vapour bars. Most times, one on the inside, immediately under the drywall or over the studs is the right one.
I might as well chime in with a quick question... My crawl space is set up like this. Foundation(not concrete but earth)--->vapor barrier(plastic)--- Insulation between the studs with the vapor barrier side down, facing the earth. I have been told the insulation should be facing the other way with vapor barrier up(against the wood) I was told I could just slit insulation to allow the moisture out but I should re hang the insulation to let it breath. Even If I hang the insulation correctly, isnt that still 2 moisture barriers? Shouls I just go wil no barrier insulation or barrier insulation hung the correct way?
JH
I'm not sure what you mean by no foundation other than earth. There must surely be perimeter walls of some kind on footings?
I'm not sure what you mean by no foundation other than earth. There must surely be perimeter walls of some kind on footings?
You need the plastic down to keep ground moisture in the ground. That is one VB in that direction from the crawlsoace.
Then you need a VB in your joist space. Which way it faces is determined to some degreee by the climate you live in. Check by sneaking you rhaqnd up in the space and through and over the insulation at butt joints. If it is dry, you are OK. Don't bother it.
You need the VB at the earliest position possible to keep moisture from going from warmer wetter areas to cooler drier areas. If your crawl space is damp and your house is dry, you want the VB on the bottom of the insulation. If you had an open crawl space that could ventilate to the outsdier and it stayed cold because of that, you would want your VB to be near the subfloor to stop warm moist air from heading towards the cold, dry underspace. Conversely, If you live in a hot damp climate like Florida or Georgia and your house is elevated over an open crawl, the warm moist air is outside and the airconditioned air inside is cooler and drier so you wouild want the VB to be on the bottom of the insulation.
