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Hy Cheese Posted: Jul 06, 2008 07:42 PM	under floor crawl space I am on a dirt crawl space with no access to speak of, even if there were I would not fit, the house sits on multiple block knee walls with one block openings to the next section (2 block high) I will be replacing the floors and will be down to bare joists. Inspection holes showed many large rocks/boulders and dirt mounds that make it impossible to navigate - did I mention the rat snakes, I have no rodents in this house. A 5 foot black snake a fat man and a 16" crawl space equals floor nails in the head. Would it be best to just put a kraft face glass in or is there an easy way to do foam from above. I thought about nailing cardboard to the bottom of the joist and spraying with foam from the top and fill the rest of the cavity with cellulose. I know the vapor barrier would be on the wrong side but will it be an issue. Or maybe cardboard-cellulose-more cardboard- then foam on top to floorboards. Thanks, cb
mason Posted: Jul 07, 2008 08:09 AM	I can see that it would be very difficult if not impossible to spray overhead in a 16" crawl space. The idea of installing the foam between the joists from the top is feasible. Since you are pulling up the floor, you could install polyethylene plastic to the dirt floor first, spray the edges and then install the foam as you describe to cardboard, fiberboard etc. That way you have a vapor retarder between the dirt and the house so a vapor drive into the house is stopped in that direction.
philip mullins Posted: Jul 09, 2008 01:47 AM	i feel your pain, bro. i have actualy had to dig trenches!sucked bad, but the rig note got paid. mason, since the floor is coming up, could he just spray down on the dirt and up the sides? maybe throw down some plastic first?
Hy Cheese Posted: Jul 09, 2008 07:00 AM	Thanks for the replies, I thought about closing the crawl space off as you said but it has about six blocks laid on their side for vents and would worry about moisture and molds since it would be impossible for me to get at 100% of the ground from above to seal everything.
Eric Sparks Posted: Jul 14, 2008 07:32 PM	i had a customer that had a 100 yr old farm house with no crawlspace, he put plumbing strap from joist to joist then put masonite down and had me spray that. it really suprised me how well it worked out.
Hy Cheese Posted: Jul 14, 2008 08:31 PM	Yeah Sparky I kinda had the same thought but was going to staple cardboard or plastic in the bottom of the joist and spray an inch of foam then top off with cellulose. Masonite may be more costly but I wouldn't have to worry about the foam breaking loose and falling down either.

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Comments

Hy Cheese

Posted: Jul 06, 2008 07:42 PM

under floor crawl space

I am on a dirt crawl space with no access to speak of, even if there were I would not fit, the house sits on multiple block knee walls with one block openings to the next section (2 block high) I will be replacing the floors and will be down to bare joists. Inspection holes showed many large rocks/boulders and dirt mounds that make it impossible to navigate - did I mention the rat snakes, I have no rodents in this house. A 5 foot black snake a fat man and a 16" crawl space equals floor nails in the head.

Would it be best to just put a kraft face glass in or is there an easy way to do foam from above. I thought about nailing cardboard to the bottom of the joist and spraying with foam from the top and fill the rest of the cavity with cellulose. I know the vapor barrier would be on the wrong side but will it be an issue. Or maybe cardboard-cellulose-more cardboard- then foam on top to floorboards.

Thanks,
cb

mason

Posted: Jul 07, 2008 08:09 AM

I can see that it would be very difficult if not impossible to spray overhead in a 16" crawl space. The idea of installing the foam between the joists from the top is feasible. Since you are pulling up the floor, you could install polyethylene plastic to the dirt floor first, spray the edges and then install the foam as you describe to cardboard, fiberboard etc. That way you have a vapor retarder between the dirt and the house so a vapor drive into the house is stopped in that direction.

philip mullins

Posted: Jul 09, 2008 01:47 AM

i feel your pain, bro. i have actualy had to dig trenches!sucked bad, but the rig note got paid.

mason, since the floor is coming up, could he just spray down on the dirt and up the sides? maybe throw down some plastic first?

Hy Cheese

Posted: Jul 09, 2008 07:00 AM

Thanks for the replies, I thought about closing the crawl space off as you said but it has about six blocks laid on their side for vents and would worry about moisture and molds since it would be impossible for me to get at 100% of the ground from above to seal everything.

Eric Sparks

Posted: Jul 14, 2008 07:32 PM

i had a customer that had a 100 yr old farm house with no crawlspace, he put plumbing strap from joist to joist then put masonite down and had me spray that. it really suprised me how well it worked out.

Hy Cheese

Posted: Jul 14, 2008 08:31 PM

Yeah Sparky I kinda had the same thought but was going to staple cardboard or plastic in the bottom of the joist and spray an inch of foam then top off with cellulose. Masonite may be more costly but I wouldn't have to worry about the foam breaking loose and falling down either.

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