Can I spray foam the inside skirting of my house?
I am trying to keep my water tanks from freezing – my water tanks are under the house. Would the house shift from this? The house is sitting on wood pads.
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Are you asking about the insulation causing the ground to thaw? Can you just spray the tanks? People leave large water tanks outside (foamed) all year in Fairbanks. I don't know how it works, but it does.
Mike,
Can you tell us where you live and describe your house a little better?
I'm visualizing a house on wooden piers, with skirting surrounding the piers. Is that what you have?
If so, I don't recommend spending lots of money on spray foam to spray your skirting. The money would be better spent on a concrete foundation. John's advice makes sense: spray the tank, not the skirting.
Do you also have plumbing pipes under your house? Are your pipes freezing?
Live Churchill, Manitoba . The building is raised on wood pads and skirted with exteriors pywood. If I foam the skirting from under the house would that effect the structure with shifting etc.?
Mike,
Do you live in an area with permafrost?
yes permafrost is about 3 ft down .
Mike,
I'm not an expert on permafrost issues, so I suggest you obtain local advice. Perhaps some GBA readers from Fairbanks will provide further comments.
In general, if you insulate around the perimeter of the foundation of a house built over permafrost, the heat from your house will raise the temperature of the soil under your house, leading to the possibility of melting. This may lead to a problem -- for example, uneven settling.
Insulating the tanks with even a foot of foam would require less foam than insulating the skirting, would freeze-protect the tanks better, and suffers no permafrost-foundation issues.