I am renovating an end-of-group brick rowhome in Maryland. The home was built in 1914 and has 8″ masonry load bearing walls. The owner is interested in exposing the old masonry walls on all (3) exterior sides of the building. To do this I will have to insulate from the exterior and install new cladding. I am not confident in installing 4″ or so of rigid insulation on the old masonry, mostly due to cost/ performance of fasteners that long into the old masonry. The rainscreen and new cladding will also be relying on the same type of fastener.
Question #1: Is there a good way to fasten all of the new exterior layers to old brick? I am ready to ditch this option for the one below:
Option 2: I am thinking about pouring a small footer and framing a new 2×6 wall outside of the existing brick exterior. The wall would be held off the wall 2 inches and tied in at 4′ intervals. I could then use a number of different insulation options (leaning toward cellulose), sheath, rainscreen and clad with more confidence in fastening.(This does mean I would have to extend the roof also).
Does this sound like a better option? Insulation type recommendations? Plenty of details to consider.
I appreciate any feedback,