Fill crawl space with foam?

[Edwin Pawlowski]

Take a peek here

They even have a book It is a more scientific approach than has been done over the years and make some sense.

[Bob M.]

How about Corbond? Since there's access to this area from the basement, it should be possible to spray the stuff on. Not a DIY job.

[L D'Bonnie]

If the bugs don't get in the water will and rot everything until the floor falls through.

LdB

[BobK207]

Joe-

!8" to 24" is a bunch of crawlspace clearance.

You've only got ~9 joist bays. If you plan the work & lay it out properly there won't be any "hugging the fiberglass".

Once you have access to the space, the stuff would be up in about an hour or so..

If don't want to DIY......you could pay someone to install it for you; you cut, they install.

Still way cheaper than foam.

cheers Bob

[Calab]

From above, along one of the outside walls, across the ends of the joists, cut a two foot strip out of the floor, then you can drop underneath and put fiberglass batts between each joist. You can then roll a sheet of plastic out and staple it to the bottom off the joists.

[marson]

I haven't heard of it, but maybe I should have. What is it, and how is it applied? Do you have a website or something you can refer me to?

[JoeSpareBedroom]

I'm not real keen on removing blocks. The existing slots are in the 2-by wood which sits on the sill plate.

[hallerb]

spray foam or minimally expanding are usually pro installs, why not call some local insulating contractors for free estimates.

will look for minimial expanding websites.

they use heated guns and such to install, thats why it generally a pro install

[Wayne Whitney]

In a heating climate, that would be unwise--the vapor barrier goes on the warm side of the surface.

Wayne

[JoeSpareBedroom]

Not on the soil underneath, assuming there was a way to seal the edges where the barrier met the cinder blocks?

[The Reverend Natural Light]

The termites that were eating my basement would disagree. Of course, they didn't bother pulling permits for their demolition.

[salty]

You have a wooden basement with a dirt floor? Most termites don't normally eat concrete and masonry.

[DerbyDad03]

Since you said that removing the sub-floor is not out of the question, you could...

- Remove the sub-floor - Crawl underneath and attach 1 x 2's perpendicular to the joists - Lay plywood strips on these supports, forming a "floor' in each cavity - Spray expanding foam insulation in each joist space - the kind you see used on TOH. - Replace sub and finish floor - Save the wooly socks for sledding

[JoeSpareBedroom]

Since you said that removing the sub-floor is not out of the question, you could...

- Remove the sub-floor - Crawl underneath and attach 1 x 2's perpendicular to the joists - Lay plywood strips on these supports, forming a "floor' in each cavity - Spray expanding foam insulation in each joist space - the kind you see used on TOH. - Replace sub and finish floor - Save the wooly socks for sledding

==================

Wouldn't I still need a plastic vapor barrier right on top of the soil? It's cheap enough....

On the other hand, this crawl space is bone-dry.

[Wayne Whitney]

There are alternatives to fiberglasss for batt insulation, like cotton or mineral wool.

Wayne

[Wayne Whitney]

Well, a few comments:

A vapor barrier in the floor system is to keep warm moist air from migrating into the crawl space, condensing there, and causing the usual problems of unwanted water. This should definitely be on the warm side of the insulation; otherwise water vapor will travel through the insulation, cooling as it does, and condense in the insulation, where it would be trapped by the vapor barrier underneath.

A vapor barrier on the soil is to keep moisture in the earth from rising into the crawl space. So it serves a different purpose. If you have a vapor barrier in the floor system, I'm not clear on whether having one on the soil would cause any problems. I'm just wondering how any vapor in the crawl space would actually escape? I guess if the crawl space walls have no vapor barrier, it can escape through that.

Lastly, I believe that a vapor barrier, unlike an air barrier, doesn't need to be perfect to be effective. I believe that have a 95% vapor barrier will give you 95% of the benefit. With an air barrier, any wind would drive the air infiltration through the remaining 5%, giving you less than 95% of the benefit. Hopefully someone else can verify that my recollection in this regard is correct. :-)

Cheers, Wayne

[JoeSpareBedroom]

All these unknowns! I have an idea that'll make this part of the kitchen really unique. It'll be obscenely expensive. I'll redesign the floor so it consists of four hinged 6x6 hatches, with hardware as shown below, for lifting the hatches. If one insulation method doesn't work, I'll have easy access for trying another, and another...endlessly. Maybe I'll use teak.

[The Reverend Natural Light]

If there were insects that ate concrete, I'd have them.

With a 1/16" gap between the slab and walls, it might have well been a dirt floor. Didn't slow the termites down one bit. It's all fixed now, but what a mess.

[Rick Blaine]

Furthermore, I'm pretty sure most code requires a minimum distance between the ground and the house structure if it isn't concrete. Providing a medium that moisture can follow or that critters can burrow up into the house doesn't strike me as the best idea.

Given the limited area involved, boxing in the underside of the joists and then filling them with insulation might be a better alternative...

[Wayne Whitney]

Oh, why is that? Wayne