had a delay in permit so I have a couple more months to eval this. Z5, Chicago (not sure if that matters). Debating 2 layers of 3/4" polyiso with 1x4 furring or just doing 2 3/4" sheets with siding nailed through (hardie). Questions:

1) kiln dried or treated furring?
2) house wrap over furring "floating" against back of siding?
3) flashing against OSB wall sheathing extend out past siding, or just attached to and screwed through the foam?
4) how do we flash where siding (with foam) will meet a brick wall (brick below siding of course)? Brick will not have rigid behind it.
5) on front of house, there will be brick. On side, it is siding. At the corner, since the thickness of the siding is approximately 3" (3/4"+3/4"+3/4"furring+siding), the brick will have to "hang out" over the edge to match the siding. Is this ok?

1) kiln dried or treated furring?
KD; no reason to use treated there

2) house wrap over furring "floating" against back of siding?
rather than housewrap, tape the joints in the sheathing; that will help the air sealing

3) flashing against OSB wall sheathing extend out past siding, or just attached to and screwed through the foam?
windows can be flashed to the foam; intersections with walls or roof should be flashed back to the sheathing

4) how do we flash where siding (with foam) will meet a brick wall (brick below siding of course)? Brick will not have rigid behind it.
flash with lead onto the sheathing and out over the brick. Leave a drainage channel above the lead so the foam does not get wet.
Any way to put foam behind the brick?

5) on front of house, there will be brick. On side, it is siding. At the corner, since the thickness of the siding is approximately 3" (3/4"+3/4"+3/4"furring+siding), the brick will have to "hang out" over the edge to match the siding. Is this ok?
Can you install a small piece of angle iron under the canteliever? If there is a brick shelf on the foundation, perhaps a piece of flat steel 12-16" on the top of the shelf extending out to within 1/2" of the end of the brick.

"Can you install a small piece of angle iron under the cantilever? If there is a brick shelf on the foundation, perhaps a piece of flat steel 12-16" on the top of the shelf extending out to within 1/2" of the end of the brick." Yes we can do this. thanks for the answers.