rodent (mice) prevention under siding
Folks, I’m slowly remodeling a 40 year old house while living in it and am almost done. Exterior walls opened from the inside reveal plenty of evidence of mice infestation over the years, especially in wiring and plumbing runs. I’ve addressed these areas with foam sealant but still have mice getting in.
I have masonite siding on top of a 1/2 in fiber board (?) that attaches to the studs. The bottom siding board is about 1-1/2 in from foundation wall and I stick a tape measure up 2-1/2 in between foundation wall and back of siding. I would like to seal this hollow cavity under the bottom siding board as I have seen mice run up into the cavity and believe this may be a major entry point. My siding is in great shape for being 40 years old and I have no other visible openings in the siding.
Question is, how do I do it?
Do they make a wire mesh/screen etc I can jamb up there to prevent entry. I was considering using foam sealant but am afraid when it cures it may cause the siding to bulge out from the pressure. The house perimeter is about 200 feet with much easier access from the outside than from under (crawlspace). Any ideas would be appreciated.
Replies
I have the same question
Expanding foam worked for me - twenty years since I sprayed it. Did not push out the siding. I don’t think you have to fill 2.5 inches, just seal the gap. The foam can expand both up and down.
I hate to tell you this, but you will have a challenge stopping mice. They do make foam specifically for this purpose, which has hot pepper or some other ingredient to discourage chewing, which you can find online. But I'm willing to bet the mice have other ways to get in as well. Mice climb well and I have seen one go up and enter a house at the eaves. So virtually anyplace is possible. I bring this up all the time with other builders but it makes no impression, so decades from now all the houses built now will have the same problem.
I had this problem in my last house. Mice were getting in through the spaces around pipes that penetrated the outside walls. It is surprising how little space a mouse can get through. Spray foam is no barrier to little animals with sharp teeth. After various failures and damage to wiring in a stove and dishwasher I hit on the idea of stuffing stainless steel from scrubbing pads into the gaps and then using low expansion foam on top to fill the spaces. Problem solved;-)