Dow Tuff-R vs, Sturdy-R
I am planning on wrapping a home with rigid foam before I apply exterior siding, actually cement fiber. I will use a air space between the foam and the siding via strapping.
My question is whether to use a foil faced product like Tuff-R (in the interest of getting a great air infiltration barrier) or something with a bit more perm like Study R (fiberglass faced) I am wondering if I should worry about any water getting behind the foam (or from the inside of the wall) and the foil faced product trapping it, where as the Sturdy-R has a perm rating of 3, Doesn't need to be a DOW product specifically. I guess I'd use a vapor barrier on the outside of the Sturdy-r such as felt or some other house wrap such as Tyvek. I like the idea of the Tuff-R as it serves well as a air infiltration barrier and it tape sticks to it well at the seams.
I plan to use about an 1" thickness and I think this should keep the dew point outside the interior wall.( assumed R-13 in wall.
I haven't investigated the price point of the Tuff-R vs the Sturdy either but most places i know don't carry it, so it would end up being a special order or I would end up buying a lift of it
Posted May 27, 2009 8:33 PM ET
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