Why are carpenter ants eating my SIP walls?
frankgrupt
| Posted in Green Products and Materials on
Why are carpenter ants eating my SIP walls? I have fine white dust on the ground
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Replies
Dampness (Foam/Sheathing)
Food/water sources near by the structure (downed limbs, trees, etc). General dampness.
Insufficient space between landscaping and the exterior walls.
Insufficient pest mitigation.
A more apt question might be: Why would they not? The foam provides a perfect nesting site that can be expanded indefinitely as the colony grows and splits.
They will need a trail to forage for food and moisture. Find out where that is. Get a professional exterminator in before they compromise the structural integrity of the panels.
Once they are gone, make sure to eliminate the causes that John listed. Why SIPs aren't made from borate infused foam is beyond me.
I’m on it!
And GET BORIC ACID AROUND YOUR FOUNDATION ASAP!
Aside from the reasons listed above, carpenter ants may just nest in foam because it's there. See:
https://www.greenbuildingadvisor.com/article/if-ants-like-rigid-foam-should-we-stop-using-it
I would love to see more written on this topic, as exterior foam (exterior or otherwise) is a major wall insulation strategy advocated here and by builders in my area.