Risk of rodent/insect damage To FPSF rigid foam
brentwilson
| Posted in General Questions on
An FSPF slab foundation (using something like this: https://bygghouse.com/warmform-slab-forms/ ) uses a lot of rigid foam under the concrete. If rodents or insects were to get into that foam, it seems that the structural integrity of the slab floor (and potentially the whole building) could be compromised. Any idea if this is an issue or concern in a place like CZ 6B in Idaho?
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Replies
Replying to a very old thread, but I will say that we recently had an issue with carpenter ants tunneling through the vertical insulation on our FPSF. Unfortunately I cannot tell you whether they got into the subslab insulation. We are in midcoast Maine.
This is a pretty good discussion about the topic: https://www.greenbuildingadvisor.com/article/if-ants-like-rigid-foam-should-we-stop-using-it
My 30 year battle with carpenter ants here in the PNW, has been that with diligence you should be able to stop them getting established inside your foundation and framing, but I'm a lot more equivocal as to whether that's possible on the exterior.
These carpenter ant bastards are damn near impossible to get rid of. You need to declare outright war creating a perimeter of at least 100 feet surrounding your house and attack not only your home but all the fallen trees and branches to get at their nests. The commute from these nests to your house and then move to a new nest when you attack that.
Take no prisoners. Use everything you've got. They still may win.