XPS is one of the least green insulation products out there, due to the HFC134a blowing agent used .(HFC134a has a 100 year global warming potential of nearly 1400x CO2.) Over a handful of decades as the HFCs bleed out of XPS it's performance drops to that of EPS. So that 1.5"/R7.5 foam will eventually drop to R6.3-ish, which is not sufficient exterior R value for dew point control on an insulated 2x6 wall, even though R7.5 would be just enough.
See TABLE R702.7.1:
http://publicecodes.cyberregs.com/icod/irc/2012/icod_irc_2012_7_sec002_par025.htm
A greener and safer-performance option at the same thickness would be to use foil-faced polyisocyanurate, which has the advantage of being easier to properly air seal. At 1.5" it's labeled R-value is between R9-R10, but loses a bit of performance when the average temp through the foam is lower than 45F or so. Fully derated it's average wintertime performance in your climate will be about R5/inch or a bit higher. So even at it's derated performance is 1.5"/R7.5 it'll still make it without interior side vapor retarders and during the shoulder seasons it will be performing at it's labeled R value (or a bit higher). Polyiso is blown with pentane (about 7x CO2), and the foil facers can be easily & reliably air sealed with housewrap tape or a temperature rated foil tape, which are cheaper than the tapes that would be needed for sealing XPS. With an air-gap between the foil facer and the siding it adds another ~R1 to the stackup performance too.
If you're mounting the windows "innie" with the glass roughly co-planar with the sheathing, the weather resistant barrier (housewrap or #15 felt) etc) needs to be between the foam and the sheathing, with the window & door flashing properly lapped to it. If "outie", with the glazing roughly co-planar with the siding, it goes over the exterior side of the foam, with a vent air gap between the foam and siding/veneer.
For the foundation walls R15 continuous insulation is IRC 2015 code-min for zone 5, even for crawlspaces and unfinished basements. This is easy to do with minimalist 2" + 2" insulated concrete forms (ICF), and 2.5" + 2.5" ICFs isn't overkill.
It's worth adding 1.5-2" of EPS under unheated slabs in your climate. Run the wall foam all the way to the inteior EPS of the ICF, and lay down a polyethylene or EPDM vapor barrier over the foam. That "floats" the slab, since it isn't in super-rigid mechanical contact with either the walls or the footing, which lowers the likelihood of cracking. Unless specifed by code, the crawlspace area can be a 2" non-structural rat-slab, but a basement floor that will be used still needs to be structural. Use 1.5lb density "Type-II" EPS, which will have sufficeint compressive strength to park your Caterpillar D9 there without cracking a 4" slab. EPS is also blown with low-impact pentane (most of which is oftn recaptured at the factory and burned for process heat) and far greener than XPS. It's cheaper per labeled R than XPS. At 2" it will be labeled R8.4, which is better than 1.5" XPS, and "sane" value for an unheated slab. (You'll want more if it's a radiant floor slab.)
Brick veneers have bit of a thermal bridge problem, since they have to rest on the foundation. Forming a 1 foot or deeper step in the ICF foundation to accommodate running the polyiso wall insulation all the down to the shelf supporting the brick, and adding foam to the top of the foundation continuous with the interior EPS of the ICF is a good idea which somewhat mitigates that thermal bridge. Use an EPDM sill gasket under the foundation sill to keep ground moisture from wicking into the sill, and use an inch or two of closed cell spray polyurethane to insulate and seal the interior side of the band joist. & foundation sill to the interior side EPS of the ICF.
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