Siding & insulation
I just bought a”distressed” property. Goal #1 is to keep the renovations as cheap as possible. Goal # 2 is to be as green as possible. I am planning to wrap the exterior with 2″ of 2nd hand polyiso (which I have piled in the living room.) It is felt-faced rather than foil-faced. Does anyone know anything about that? Question #2: I’m concerned about getting moisture in the walls. There’s no interior moisture barrier and I’m not planning to rip out the interior walls (except where I need to put in new plumbing, wiring & windows, which is quite a bit). The walls are drywall, 3″ foil-face fiber glass poorly installed, plywood, composite lap siding. (vinyl siding is gone.) I as planning to put the polyiso over the lap siding and seal thoroughly. Feedback? Any suggestions for siding? I was thinking about putting the vinyl siding (which is piled in my yard) back on until I can afford something more attractive.
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Replies
Diane,
Q. "I am planning to wrap the exterior with 2 inches of second-hand polyiso (which I have piled in the living room.) It is felt-faced rather than foil-faced. Does anyone know anything about that?"
A. Either type of polyiso will work fine for your application. Needless to say, pay attention to airtightness when installing the rigid foam; include a water-resistive barrier (WRB) that is integrated with the window and door flashing; and make sure that the rigid foam is all the same thickness so that your installation is co-planar.
Q. "I am planning to put the polyiso over the lap siding and seal thoroughly. Feedback?"
A. See the answer to question #1. Hopefully, you have a good grasp of moisture management principles and flashing techniques. If you don't, it's time to study up, or to hire an experienced contractor.
Q. "Any suggestions for siding? I was thinking about putting up vinyl siding."
A. Vinyl siding will work, as long as you are willing to install it on furring strips. For more information, see Can Vinyl Siding be Applied Over Furring Strips?