Vapor barrier in tight crawl space
Salz320
| Posted in Energy Efficiency and Durability on
I have a sloping crawl space under a 100-year-old Virginia house which does not have any termite or rot damage that I can find. At the tightest end of the house, there is less than a foot of crawl space.
There is very, very little space to move around in this crawlspace.
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Replies
Randy,
I think you forgot to ask a question.
If you need more room to crawl around down there, you'll need to excavate the soil and remove it in buckets. Get out your entrenching tool and get to work. Be careful that you don't undermine your footings; if you aren't sure of the protocols for lowering the floor near crawl space footings, talk to an engineer or an experienced concrete contractor.
If you want information on crawl space moisture problems and installing a vapor barrier on your dirt floor, I recommend that you read this article: Building an Unvented Crawl Space.
Thank you, Mr. Holladay. That is an excellent article and I appreciate your turning me onto it. Since I simply cannot dig out this crawl space even if I had a hundred people to pass buckets, it still leaves my question.
My question was primarily "is it helpful to put a vapor barrier (6 or 10 mil) wherever it is conceivable to get one? I know that I can't cover all the dirt in the crawl space but I might be able to cover 1/3 to 1/2 of it (and even that will be very difficult).
If I do so, is covering the space partially simply a waste of time and/or money?
Thank you again for your response.
Randy,
You should certainly cover as much of the dirt as you can with a polyethylene vapor barrier. Even if you can't cover 100% of your floor, cover what you can.
It would be even better if you could hire a contractor to lower the level of your crawl space floor (to improve access) and then cover 100% of the dirt with a polyethylene vapor barrier.