My wife’s parents house has a 4 foot crawl space with a gravel floor. They live in St John’s Newfoundland where the climate can be quite wet. Over the past couple of years the support beams (laminated 2×10’s) are showing signs of rot. The underside of the entire floor is covered with 2 inch thick styrofoam insulation. The floor joists are showing very little moisture damage. The 4 foot concrete wall is not insulated, but there are a few small openings for ventilation. The 2 support beams which run the full length of the house (48 feet) need to be replaced and the moisture problem needs to be fixed to prevent any future damage.
Any thoughts, comments, and ideas will be greatly appreciated.
Thanks
Replies
Steve,
Welcome to Breaktime!!
If you click on your name above (where it says "To: SteveNFLD"), you will open your profile.
We would appreciate it if you could fill some of that in.
Thanks!
Regarding your problem...I'm inclined to think that the crawl needs to be sealed. This means that a heavy poly covers the floor of the crawl and is run up the walls and any piers and sealed with mastic. Any seams in the poly should be sealed with mastic. Any vents to the outside should be sealed closed.
Then remove the styrofoam and use it against the perimeter walls of the crawl. Or if it cannot be removed without destroying it, then get new 2" styrofoam.
Finally, find a unobtrusive spot to put a hole in the living area floor, run a duct a few feet from the hole and stick a fan (moving about 1 cfm of air for each 50 square feet of crawlspace) on the end of it.
If there is a lot of water down there, then you might want to put in a sump pump to begin with. You don't want a body of water under the plastic.
Disclaimer: I am working almost entirely off of what I've learned from magazine articles and threads here at Breaktime. I do not (yet) have any experience at doing this (but I've currently got three bids out to do so!).
Rich Beckman
Another day, another tool.
Rich,
Thanks for the welcome and the response....I have updated my profile as requested. A local contractor suggested spreading a layer of crushed stone, covering it with vapour barrier, and then pumping in a layer of concrete to cover it all. He also recommended adding styrofoam to the concrete walls as you did.
Any thoughts on this idea?
Steve,Thanks for filling in the profile.Regarding the pouring of the cement...First I will refer you back to my disclaimer:"I am working almost entirely off of what I've learned from magazine articles and threads here at Breaktime. I do not (yet) have any experience at doing this (but I've currently got three bids out to do so!)."I guess I left out of it that I have also learned alot by being in a lot of crawlspaces over the past few years. I relate what I read to what I've seen in crawls.I've never been in a crawlspace that had a slab for the floor. And for all intents and purposes I've never worked with concrete. So I really cannot competently comment on that plan.My incompetent comment would be...I would detail the vapour barrier very carefully, sealing the seams, etc.I have no idea if it should run up the sidewalls or not, but I'd be inclined to do that and then seal it to the block. So the slab would be completely contained by the poly.In other words, I would do what I said in my first post and add the slab.But I would try to get some imput from other more knowledgable than me before I did it.Rich BeckmanAnother day, another tool.