The Xcluder Single Roll is rust-proof and will not stain.
It is not recommended to seal up holes or crevices if you have current rodent activity until they are removed. You do not want to seal them up trapped inside the voids because this could lead to odor and other insect activity. We carry excluder traps and then the holes can be sealed. It is also very helpful that you treat with a general pest control product such as Bifen IT to eliminate the insects that the woodpecker is attracted to. I have included some articles below that you may find helpful. Please let us know if you need anything else.
Xcluder Single Roll (4 in. x 10 ft.) is not officially fire rated, just like the carpeting in your home is not fire rated.