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I’m adding 1200 sq ft of floor inside of a “crawlspace” that has 12-24 feet of headroom. As I’ve been working on this project, I’ve noticed that mice have nested in the insulation (unfaced) that is installed between the floor joists of the upper floor. Once I close off the new floor with drywall, the back sides of the new walls will have unfaced insulation exposed to the crawlspace and those darn mice will most likely move in.
If the walls are finished with drywall, vapor barrier and then insulation, I’m wondering if I can seal off the *back* side of the insulation to keep the mice out. Same goes for the underside of the floor. I know this may trap moisture and cause rot, so I’m looking for something new.
Otherwise, I’ll just go buy a bunch more D-Con and hope for the best.
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Dear Crawl space builder,
I admire your custom building efforts to accommodate statuesque people. Sadly, smaller occupants have also found the space appealing.
There is no worry about trapping moisture in your walls. You see, water will not condense unless there is a cold place to chill the vapor into liquid. In your case, if I understand it correctly, the back of the walls are bound to be about as warm as the front side. Despite a bit of confusion about the geometry of the building, any place mice dwell has open bypasses between the indoor and outdoor spaces.
Would you believe that just last week I was privileged to attend presentations from two young ladies, one from Montreal and the other from Sweden, who were studying the effects of mouse tunneling in insulation? From what I gathered, unless you seal things up very tightly, you may want to add an auxiliary heater to D-con for your shopping list.
Shortly, Fred
*What about stapling up wire mesh? Heavy duty screen should keep the little furries out.
*Although I'm somewhat baffled by parts of your post the most effective way to seal off the 'outside' face of your new walls would be to treat them like they're outside walls. Sheath them with some tight fitting, cheap material like panelling, or 1/4" chipboard(aspenite). If you frame your walls on the deck, sheath them before standing them up, and then fill the shim space at the top plate with foam (sprayed or rigid strips).If your new room is going to use the existing ceiling above as its ceiling, and you're going to heat the new space, you should remove the old insulation in that ceiling to provide for a warmer floor in the rooms above.
*Leave out the decon. Here in Hanta virus country the smart bet is on 1/8" H.W. cloth installed very carfully being sure to cover any possible entry.Don't let the your worst laborer do it unsupervised. If you have a mouse problem now,use live traps to make sure you are making progress against the critters. Dead mice carry the virus.
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I'm adding 1200 sq ft of floor inside of a "crawlspace" that has 12-24 feet of headroom. As I've been working on this project, I've noticed that mice have nested in the insulation (unfaced) that is installed between the floor joists of the upper floor. Once I close off the new floor with drywall, the back sides of the new walls will have unfaced insulation exposed to the crawlspace and those darn mice will most likely move in.
If the walls are finished with drywall, vapor barrier and then insulation, I'm wondering if I can seal off the *back* side of the insulation to keep the mice out. Same goes for the underside of the floor. I know this may trap moisture and cause rot, so I'm looking for something new.
Otherwise, I'll just go buy a bunch more D-Con and hope for the best.