I have to replace several failed Pella Casement windows, and while doing so, I plan to upgrade the siding from vinyl. And if I have the siding off, I might as well install some 1.5″ thick Rockwool 80 exterior insulation with vertical 1×3 furring strips to create a rainscreen. I understand the use of the Cor-A-Vent screens at the top and bottom of the furring strips, in the same plane as the furring strips. But, should there be something to protect the bottom of the Rockwool insulation to prevent bug/rodent intrusion? From what I have read, the Rockwool will not totally prevent the little pests from tunneling into it to make homes…Any suggestions?
Thanks,
Anthony
Replies
Yes, use foam board rather than rockwool. Much higher R value and water proof to boot.
I do prefer foam board for ease oof installation but Rockwool/Thermofiber is frequently used behind rainscreen in commercial construction. It can tolerate being saturated and loses no R value when it dries out so you dont need to rule it out.
But why mess with floppy, hard to install 1 1/2" thick rockwool when you can install 3/4" foam board faster, neater and have the same R value?
Agreed. Thats why I said I prefer foam board!