I really appreciate all the great feedback from the forum members on various questions.
We are working on lots of renovations to our home that is located in Toronto, Canada. It was built in the early 70s and the external walls are built 2x4 studs with Gyproc sheathing, 1/2" air gap and 4" brick veneer. On the inside there is 1/2" drywall, no vapour barrier and R7 fiberglass insulation with kraft paper facing. Pictures included below.
We needed to open many of the exterior walls for the renos but not all. However it appears that R7 is no longer adequate in terms of insulation so we bit the bullet and asked the contractor to open up all exterior walls to replace insulation everywhere.
What insulation should we be replacing with? Some of the insulation that was removed from walls has black markings. Is this of concern or point to a possible issue?
Any pointers from the experts would be very helpful. Thanks