Spray foamed crawlspace, now think I screwed up.....advice??

D-rock · 01-22-2012, 11:22 PM

To start of, here is the history. Last year I noticed the fiberglass insulation in the crawl space was falling off the walls in some areas. I inspected those pieces and found them to be a little wet. I removed all of it and threw them out. Throughout the summer I noticed some wet/damp areas on the walls, but never any standing water or puddles. As the weather got colder (Ohio) I noticed the floor above the crawlspace to be colder then normal. I did some research and decided to spray foam the area.

I had an estimate and when they inspected it they said the moisture wasn't anything to worry about and the closed cell foam would take care of everything. (moisture barrier and air barrier)

So.....I spray foamed my crawlspace this week with closed cell style foam from gravel floor of foundation to the top of the sill plates.

Now I find some info saying that ANY water/moisture weeping or leaking in through the foundation/bricks may wick up the wall behind the foam and rot away the wood of the sill plates.

Did i make a mistake doing this? It made the crawl space much warmer, drier, and the bedroom floor above it is nice and warm.

Should I cut a one inch channel parallel to the top of the foundation just below the sill plate to allow any water to leak out? Maybe cut one along the bottom too?

FWIW...the slope around the house is going away from the house, the house was built in 1987, and the section of the true basement is completely dry.

**Gary in WA** · 01-23-2012, 12:16 AM

You may be in a termite zone where you would want an inspection area slot in the foam at the bottom- before they hide their tunnels or eat it; http://termites101.org/termite-basic...ites-by-region
If the walls are insulated for a "condition or closed" crawl, it needs air movement to meet code: http://www2.iccsafe.org/cs/committee...E_06_64_07.pdf

Did you have any Radon testing done before closing the crawl?: http://energy.cr.usgs.gov/radon/rnus.html

Are you required to cover the foam with an ignition barrier, per manufacturer, or local AHJ?: http://www2.iccsafe.org/cs/committee...E_06_64_07.pdf

http://www.buildingscience.com/docum...ance-and-codes

Gary

D-rock · 01-23-2012, 07:53 AM

Quote:

Originally Posted by GBR in WA

You may be in a termite zone where you would want an inspection area slot in the foam at the bottom- before they hide their tunnels or eat it; http://termites101.org/termite-basic...ites-by-region

NOT A TERMITE ZONE AROUND HERE

If the walls are insulated for a "condition or closed" crawl, it needs air movement to meet code: http://www2.iccsafe.org/cs/committee...E_06_64_07.pdf

THIS IS A VENT-LESS SPACE, THEY COVERED NOTHING THAT WASN'T ALREADY COVERED. NOTE; A SECTION OF THE CRAWL IS WIDE OPEN TO BASEMENT FOR AIR MOVEMENT, NOT CLOSED OFF AREA.

Did you have any Radon testing done before closing the crawl?: http://energy.cr.usgs.gov/radon/rnus.html

I DID NO SUCH THING

Are you required to cover the foam with an ignition barrier, per manufacturer, or local AHJ?: http://www2.iccsafe.org/cs/committee...E_06_64_07.pdf

AS PER INSTALLER, IS MAKES AS ITS OWN IGNITION BARRIER, NEEDS NOTHING. AS FOR CODE, DON'T KNOW

http://www.buildingscience.com/docum...ance-and-codes

Gary

My real concern is if I just put a band aid over a moisture leak that may now be trapped to give me future problems.

**Gary in WA** · 01-24-2012, 07:31 PM

SPF is permeable enough not to worry about it..... Cc is not a total vapor barrier (like poly) unless 13" thick. Any moisture will not effect the cc- just drain down to the dirt, unless a pressure/temperature difference effects the vapor drive coming through the concrete wall.
Mostly it will evaporate in the air-space there and condense elsewhere on a cold surface. Check with your local AHJ on the code required ignition barrier. Be certain to cover the crawlspace dirt/gravel with plastic, mastic to the wall foam.

Gary