Brick Veneer – Adding Insulation
I’ve seen many variations of this question asked, but I haven’t seen a clear answer (or maybe I misunderstood them!) so please direct me to existing resources if they exist. I remodeled a bathroom in our two story brick veneer 1960’s home, zone 5. Exterior wall construction is as follows: brick veneer, air gap, Nu-Wood fiberboard sheathing attached to studs, two layers of 3/8″ drywall. During the bathroom remodel I added kraft faced fiberglass batts, 4 mil plastic sheeting, and then 1/2″ drywall to the one exterior wall. Was adding the plastic vapor barrier and/or using kraft faced batts a mistake? This was only done in one room and I have no plans to do it elsewhere. Thanks in advance for the advice.
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The poly and kraft facing is redundant, generally you pick one or the other. There is nothing wrong with putting both just not needed.
There is nothing wrong with your wall assembly in cold climate, this is very common around me (north edge of zone 5) and works well. You want a warm side vapor retarder as you wall will dry towards the air gap behind the bricks.
The important part of any bathroom remodel is air barrier continuity especially if you have one side of the tub against the outside wall.
It is all too common to put nothing behind the tub besides the batts which is a giant air leak path into your walls.
Since you have the poly, that should be detailed as your main air barrier. Make sure this is carried all the way down to the floor, all the seams are taped and caulked around the edges to air seal. The poly should not stop at the top of the tub, it needs to continue all the way down to the bottom plate.