Siding on 1-inch Comfort Board mineral wool – REVISED
I plan to build a new house this spring. It will be std 2×4 construction with zip board sheathing. I would like to install 1″ of mineral wool board (comfort board or thermafiber rainbarrior) on the outside. Building site will be in St. Louis, Mo. Can I fasten LP Smart Side (Diamond Kote) 4 x 8 ft. panels with battens, straight over the comfort board (or equiv.), without furring strips? If so, do I use screws or nails? Do I need drain wrap between the siding and the comfort board? Thanks for your input!
Update to Question – a few more details:
This house will be on a farm with LOTS of critters that would love to take residence in a hollow rain screen cavity. (think mice, snakes, wasps, etc). I know about bug screens – but I’m afraid that mice will find a way to get through.
Also, the reason for this comfort board is to expand the wall 1 inch beyond the foundation. The basement is a walk out and the vert. siding will extend to cover the foundation on the sides and back. But you need to fur out the concrete basement walls to put siding on. So I was going to use ripped 5/4″ deck boards as the foundation furring strips (actual thickness = 1 inch, same as the comfort board). Then the plane from ground to roof would be even.
So how’s this for a compromise: fur out the 2×4 walls with 5/4″ ripped deck boards, the same as is used on the foundation walls. Except, rather than placing them over the wall studs, put them midway between the studs, attached by screw at the wall sole plate and top plate. They would be glued to the zip board and stapled from the inside wall cavity to hold them tight as the glue drys. Then I put comfort board between the furring strips, thereby reducing thermal bridging, as they would “cover” the wall studs. Thus, no “hollow” rain screen to invite nesting.
I could use 1″ wide perforated metal bug screens on the bottom to foil the mice. Plus, they don’t like mineral wool. Now the next question is:
Do I need a drain wrap between the siding and the comfort board or will the permanence of the mineral wool (50 perms – and hydroscopic to boot) be enough?
Thanks again for your input!
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