The book distributed by 475 recommends insulating thick brick walls on the interior with cellulose or fiberglass insulation — a controversial method. When asked about this approach, building ...

Q: Is it a good or bad idea to insulate house walls if the exterior is brick and the interior is plaster? It’s been recommended that we insulate our walls. The house was built in the 1940s.

Cavity wall insulation The gap between two brick walls is filled with material that has a lower thermal conductivity than air. This is because it contains trapped air which cannot transfer energy ...