Working with a prefab Gunnison home (c. 1953), which has 2″ thick exterior walls–prefab panels of 1-1/4″ studs with 3/8″ plywood interior and exterior.
The exterior of house is covered with 3/8″ foam backer and vinyl siding.
I want to apply 3/4″ furring strips to interior walls with rigid foam insulation between the strips, covering all with 1/2″ drywall.
Question: Will having insulation on the interior create a moisture/condensation issue?
Replies
In your climate, the interior is where the foam panels belong.
The concern is that you already have a foam exterior so you could end up with a dbl VB trapping moisture between the two of them.
But from what I have seen of those places, having worked on six or seven, the walls are still going to be leaky enough to vent.
But I will suggest a diffeen5t way to install :
Glue the panels to the existing interior wall surface without cutting them. Be sure the glue is right kind. If you have EPS foam, don't use most const adhesives. PL 300 is formulated for foam. Or use spray foam from a dispenser gun. It is a polyurethene glue as well as a polyurethene foam. But be sure to hold sheet in place as it kicks.
This will reduce thermal break where your method would still allow cold spots.
To fasten SR, either mark where existing studs are and screw into them, or furr out over the foam boards screwing the strapping/furring through foam and into existing wall. Then attach SR to it.
Welcome to the
Taunton University of Knowledge FHB Campus at Breaktime.
where ...
Excellence is its own reward!
Thanks!
I like your way better than mine, and you have eased my mind on the vapor barrier issue.
I will proceed with confidence!
How thick is your foam, what kind, and do your walls have a lot of shake/flop to them?
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
Just recently replaced the front door, and everything was solid and perfectly plumb.
I was going to use 3/4" foam.