I built a cottage in northern Ontario a few years ago and neglected to create a vapour barrier in the crawl space. The foundation is block and the floor is well-drained gravel; but, there is noticeable moisture on the floor joists in the spring as discussed in a FineHomeBuilding article last year #153. I have two good vents. There is not a local supplier of the material described in that article and I am looking for a substitute that I can put in the crawl space and avoid having to put down sand over top of the barrier to protect it…. I will only ever go into the crawlspace if there is a problem to fix so maybe once every three years e.g. very low traffic. Can anyone suggest a strategy and material…. somehting heavier than 6 mil. vapour barrier.
PS The cottage is wonderful and has received lots of inspiration from Tauton. I cut and milled my own lumber/timbers and it sits on 200 acres looking out at a pristine lake and I’m always adding outbuildings.
Thank you
Stephen
Replies
how about EDPM sold as pool liner for yard ponds at Home Depot can be fastened to concrete walls using Premium PLus adhesive also sold there
No matter if you have well-drained gravel the moisture is coming up thru it. Is you can't get CSA app'd VB, then straightforward heavy plastic will do. Comes in 500 sf or 1000 sf rolls. Lay it over the gravel and lap up the walls 3"-4", and keep in place w/ rocks or handfuls of gravel. Lap the joins min 12".
If a problem persists - and U R asking for trouble if it does - put an extract fan tied to a humidistat at one of the vents.
cheers
***I'm a contractor - but I'm trying to go straight!***