Interior paint/dry to interior assembly
dfvellone
| Posted in General Questions on
How critical is my interior paint-type selection for a wall assembly in climate zone 6 that’s expected to dry to the interior?
Wall assembly from inside to out:
Skimcoat plaster
5/8 imperial board
Membrain
5 1/2″ rockwool
2 1/2″ xps
Tyvex
1″ gap
Wood siding
Thanks, Daniel
GBA Detail Library
A collection of one thousand construction details organized by climate and house part
Search and download construction details
Replies
That’s a pretty safe wall assembly: you have a good ratio of interior to exterior insulation, and you have a smart vapor retarder on the interior. The exterior rain screen gap is a plus too. You should be safe using any interior latex paint in the usual way. I’d avoid using vapor barrier paints; but since those tend to be specialty materials, you’re unlikely to be using those unless you specifically request them from your paint supplier.
Bill
Where is your air control layer located? Are you using structural sheathing?
I agree with Bill that you don't have to worry about choice of paint. Even if you ended up with a vapor-retarding, class-2 paint, it should still perform well unless there was a problem that introduced water to the assembly.
The exterior ridgid foam is the air control layer, but I also detailed the membrain so it would also function as an effective air control layer.
There is no structural sheathing, i.e., plywood.