We recently bought a 1952 home in Tulsa, OK with brick cladding, plywood (I think) sheathing with drywall & no insulation in the exterior walls. We are thinking about using Retrofoam www.retrofoam.com - but their normal procedure with brick cladding is to foam the air gap between the brick and sheathing. I am concerned about the effects of filling the air gap, esp concerning moisture effects on the brick, sheathing and drywall. DO NOT want to cause any mold problems or bigger messes (rotting sheathing, crumbling brick)!

They can go in from the inside & fill the space between the studs. Not my favorite solution, as we just paid to have the whole inside painted. I am concerned about moisture problems with this also, because as I understand it, Retrofoam acts as a vapor barrier, and I believe in my climate, vapor barriers should not be placed on the inside. But unsure about this, because of the foam sealing both at the back of the drywall AND the inside of the sheathing. The differences in the foam insulation from standard insulation has me confused on the vapor barrier thing.

If the retrofoam won't work, what is my best option without taking out the drywall? I will reluctantly patch interior holes if needed. The ideal solution would go in through the mortar joints, but I am starting to think that may not work.