How do I replace brick mortar with something more insulating?
I was an associate of an energy consulting firm in 1973.
A Canadian study showed the virtues of insulating basement walls well below the frost line because of heat flow into the wall, up, and out at grade.
From then on I always insulate basement walls, as the first step in reducing energy costs. I typically use 2″ Styrofoam, mastic to concrete, brick or rock. One job, 1893 Victorian, we would put up the panels against a craggy rock wall, hammer with rubber mallets to cause high spots to indent the foam, then apple mastic there. It worked fine. Finished with 5/8″ sheet rock, just 2 long screws to the sill for fire code, then tape and popcorn finish. Eighteen years now, it is a fine way to finish a basement with no studs and no other vapor barrier.
Now. I am to insulate an existing brick building. This is not the multi-brick type as described https://www.greenbuildingadvisor.com/blogs/dept/musings/insulating-old-brick-buildings
The owner wants to expose the brick on a side that faces a cold room of a later addition to the building.
So, I can use Styrofoam again and fasten the sheet rock using lead inserts at the top.
I want to stop heat flow from this interior brick wall to the outside wall to which it is linked with mortar. This means to drill out a zig-zag of mortar near the cold outside wall and filling the gap with an insulating binder.
As an engineer, I know that polyurethane foam and Styrofoam have enormous load-bearing capabilities. I could also consider a 2-part urethane caulk or a 2-part epoxy. Of course, we want the load-bearing and locking to be as good as mortar.
So. Has anyone done this? If so, using what? If not, comments are most welcome.
P.S. picture of the building is attached. The addition is on the rear side, so looking at the picture, beyond a grade-level entrance on the left side.
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