I’m getting ready to lay up over 3000′ of fibre board siding and would like to solicit opinions about caulking the underside gap of the overlay between rows. I have heard multiple opinions, mostly about the caulk separating after a long period of time. I am thinking of using paintable silicon for extra long life. Other thoughts have addressed ‘breathing’. Each row (6″ reveal) will be about 12′ long and about 12′ high. What do all of you think?
Thanks
Jim
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Don't caulk the seams.
Liberty = Freedom from unjust or undue governmental control.
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Don't caulk them.
Your extra long life caulk will fail unless you put a very large (3/8") stretchy bead on it. Caulk needs some thickness to stretch. Silicone is not usually a good choice outside.
Bob's next test date: 12/10/07
Edited 2/8/2008 4:13 pm by Jim_Allen
Two things can happen if you caulk the planks:
1) Your caulk won't fail, and any moisture that gets behind the planks will never get out, causing mold and rotting, or
2) Your caulk will fail and you may as well not have used it in the first place. But at least things won't rot.
Take your pick.
Mike Hennessy
Pittsburgh, PA
Good and funny post Mike. Thanks. Bob's next test date: 12/10/07