Yet another crawlspace to seal
I have a 50’s era cottage in Muskoka that I’m thinking of renovating. We are not the original owners, and it has been renovated previously, with mixed results. It has a pier foundation, i.e. wood-framed exterior walls, and a dirt floor (including some tree stumps that were never dug out). The previous owners sprayed expanding foam insulation on the exterior walls to seal them (a good thing), but on the floor, they just dropped sheets of vapour barrier that are not sealed to the wall or even to each other, with holes cut in them to allow the tree stumps to stick through. Needless to say, I have a moisture problem I’m not sure how to solve (the crackers go mushy in the cupboard, mould on the walls, etc.).
Complicating matters somewhat, a number of small furry friends have taken up residence, as there is no barrier to prevent their entry. They’ve tunnelled under the wall where necessary, running under the vapour barrier (amusing to see the first time), and chewing thru the foam.
The stumps need to go, that’s obvious. The question is, how do I solve the rest of it?
— Do I just put down several layers of the black plastic? If so, how do I seal around the mechanical systems (furnace, oil tanks, water heater, etc).
— How do I seal the plastic to the foam sprayed walls?
— How do I keep the critters out? Plastic doesn’t seem to cut it, and I can’t wrap the foundation in steel wool. (or can I?)
— I’ve heard of another solution involving putting down a layer of sand, followed by the plastic, followed by sprayed-in concrete (some of our crawl space is only about 12-18″ high), but haven’t been able to find any examples. Is this a known system?
Thanks in advance (and apologies for the long message),
Bear
Replies
Bear,
Welcome to Breaktime!!
If you click on your name above (where it says "To: Bear"), you will open your profile.
We would appreciate it if you could fill some of that in, especially where you are located!! (Yes, I know. You already told us you live in Muskoka, but not everyone is going to go to the trouble of looking it up to see that it is in Ontario!)
Thanks!
"-- Do I just put down several layers of the black plastic? If so, how do I seal around the mechanical systems (furnace, oil tanks, water heater, etc). "
A lot of people use this product, one layer is sufficient:
http://www.energyfederation.org/consumer/default.php/cPath/21_933_68
You have a furnace, oil tanks, water heater, etc. sitting on the floor of your crawl??? I gotta think that's a big complicating factor and I'm not sure how to deal with that.
"-- How do I seal the plastic to the foam sprayed walls?"
Call the people at RCD and ask them.
http://www.rcdcorp.com/
Be sure you know what kind of foam it is on the walls before you call. I plan to use RCD #6, but I won't be sealing to foam. You should seal any seams in the plastic, too. Ask if the same product for the foam will work there too (if their answer is #6, then it will).
"- How do I keep the critters out?"
I don't know that one.
"Is this a known system?:"
I believe so. It might require some reinforcing wire in the slab. It would also be very difficult to finish in the areas that are only 12"-18" high.
Rich Beckman
Another day, another tool.
Good evening Rich -- thanks for the welcome. My profile, such as it is, has been updated though it's pretty thin at this point.ALL of the mechanicals are on the dirt floor, or small concrete pads (patio stones for the furnace, 12"x12" concrete footers for the oil tanks, ??? under the water tank). Part of the strange nature of the previous owner's reno. I'm currently at a loss for this one too - might try to either lift them temporarily to slide the plastic under, or seal to the edges and hope for the best (not my first choice.Thanks for the other pointers.Bear