T1-11 residing with cedar shingles
Hello, I’m a subcontractor and homeowner in a neighborhood of late 70’s T1-11 clad ranch homes. I’m changing windows and shingling my own home and hearing from neighbors that they are interested in having similar work performed on their homes. In my case, a previous owner had beveled cedar siding put directly on the existing painted T1-11 in the early 90s. In the case of one neighbor in particular the existing exterior is painted t1-11.
When I did the side of the house most severely hit by rain I found some rot on the T1-11 and decided to rip down to studs and re-sheet in plywood, then tarpaper, with shingle siding. I was also concerned with having tar paper against the studs, then T1-11, then another layer of tar paper, then shingles.
But now that I’m on to more protected sides of the house I find the T1-11 under the bevel siding to be in good condition and I don’t want to rip it off. Rather I’m thinking I will keep it, add a layer of #15 tarpaper, and shingle. Is there cause for concern having T1-11 sandwiched between tar paper? And does it justify ripping everything off on a historically dry side of a house? Would it be better to shingle directly to the T1-11 same as the crew before when they added bevel siding in the 90s?
My thinking is that painted T1-11 can’t be that different from the new zip system sheeting. Ha, anyway, sorry for such a winded question. Finally, on homes with the original T1-11, can one in good conscious (assuming the plywood is solid) reside directly on top (seemes to have worked fine for nearly two decades at my house)? And if residing ontop of T1-11 sounds resonable, do you add a WRB (tarpaper) or not?
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