My brother just built a 20 x24 family addition with a 5 foot high crawl space. He insulted the outside walls but not the floor joists as it stays warm enough. He wants to use the crawl space for storing a few things but does not want to walk on the plastic every time. Right now the floor is covered with 2-B stone. Is the plastic needed for moistue control or can he leave it as it is?
Thanks
Roy
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IMO you need the plastic. We just did one, only 24", but we laid plastic and then put pea gravel on top. If hes concerned about walking on the plastic why not install a cement floor?
BTW if he used rigid insulation for the walls, did he cover the rigid with drywall? The inspectors in michigan require a fire block on the rigid.
He's to cheap for a concrete floor, I think he should plastic it and get another load of stone to cover it. No code here requires drywall over foam insulation in a crawl space.
Thanks
Roy
Where are you located? Its kind of a pain, but I guess it makes sense to install the drywall. I guess if the rigid burns it will give off noxious gases.
There's no cure for frugality, but just remember the old saying about spending a dollar to save a dime.
Edited 1/14/2006 4:44 pm ET by MSA1
He should at least insulate the perimeter of the floor system, the box beam.
I would have done poly then a rat slab. Kind of a wet mix of concret about 2"thick.
Eric
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He should use the plastic, but even then shouldn't store anything vulnerable to moisture in the crawl (even is in plastic storage containers.)
I concur with the others above. Plastic is needed. It keeps the moisture in the ground from going up into the structure which can really reek havoc with a house. . BTW - what is 2-B stone? Stone classifications are highly regional and often set by the state DOT and are dependent of what kind of stone is locally available. If B-2 is a rounded stone (like pea gravel) he could install TuTuff plastic (or a similar high strength film) over it and it will tolerate some foot traffic. If B-2 is more of a sharp stone, the stone could be covered with either stone dust or sand or similar and then the plastic film could be installed.
My state also requires rigid foam plastics to be covered in accessible areas where any kind of serviceable systems like HVAC units, ducts, sewer cleanouts, etc are located. I think some rigid foam with foil covering is acceptable.
I'm located in Central PA, State College
2-B stone is clean stone, no screenings about the size of maybe a third of a golf ball.
Thanks
Roy