Replies

1. 
   Bob_Walker | Mar 07, 2001 01:33am | #1

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   Kyle,

   Most folks line the floor of the crawls with viz queen (heavy plastic) and control water outside to keep it out of the crawlspaces.

   A concrete floor is a great idea but there's no simple answer as to whether its "worth" it.

1. 
   Gabe_Martel | Mar 07, 2001 02:34am | #2

   *Kyle,The answer is dependant on the problem or cause of the rot/mildew.Does the crawl space flood at any timeor get wet at any time of the year? If so then you would want to install some type of drainage BEFORE you consider closing it off. If this occurs, you would want to dig a trench around the entire perimeter of any crawl space, about a foot or so deep, sloping towards a pit or drainage system, insert a 4" weeper and cover with clean crushed stone.Once you are satisfied that you no longer have any water problems, you can focus on moisture protection.A layer of heavy plastic, sandwiched between two layers of sand. Bring the plastic up the sides to the sill plates.Just some thoughtsGabe

1. 
   Dan_Morrison | Mar 07, 2001 03:23am | #3

   *Yeah, a concrete floor isn't going to keep your crawl space dry unless you lay down plastic under the concrete. So why bother with the concrete?If you're trying to stop moisture, do as Gabe says -- ensure no runoff is coming in by sloping ground away from house and maybe a drainage ditch around perimeter filled with gravel. Lay thick plastic over the dirt, overlap the seams by 6-12" and seal them with either spray foam or roofing tar. Run the edges of plastic up the walls and seal with roofing tar as well.This will be a lot easier now that the floor boards are off. Good luck,Dan

1. 
   Jeff_Clarke_ | Mar 07, 2001 03:26pm | #4

   *Gabe - I respetfully disagree with extending the vapor barrier over the sill plates - it gives cover for termites and carpenter ants to access what in his case are clearly tasty untreated wood sills set directly on the stone.Clearly the dirt requires termite treatment before a vapor barrier (8 mil or 10 mil) and the concrete offers not only protection from contact with termiticide but also rodent-'proofing' (to the extent that rodent proofing is possible) along with protection from physical damage.Jeff

1. 
   Gabe_Martel | Mar 07, 2001 04:40pm | #5

   *Jeff,I think I said "to the sill" and not over anything.Gabe

2. 
   Jeff_Clarke_ | Mar 07, 2001 05:31pm | #6

   *Yep, you did - sorry. But even 'to' the sills offers cover for shelter tubes so they won't readily be seen. In a new structure it's not too important, but in this condition (sills are probably 4 x 8 timber) the sills must be protected. Termites love stone walls, too. Their favorite path to sills is up behind the wood frames of basement windows.

3. 
   John_Sprung | Mar 07, 2001 11:31pm | #7

   *Concrete won't help with moisture control, except to protect the plastic. For that purpose, it would be way overkill. The only reason for putting concrete in part of the crawl space, after you've solved the moisture problem, would be if you wanted to use it for storage. You could stash the rakes and lawn mower down there, maybe a long ladder.... ;-)-- J.S.

2. 
   Kyle_Meadows | Mar 07, 2001 11:31pm | #8

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   Hello! I have a 150 year old ballon frame farmhouse with a stone foundation and several dirt floor crawl spaces. I have ripped out the wooden floors above the crawl spaces because of rot and I am wondering if it would be a good idea to have concrete poured over the dirt before rebuilding the floors. Now would certainly be easier than later, but is it worth the money? What are the pros and cons? The house is in Cincinnati. I can be emailed at [email protected]