Hello everyone!  I have been gathering a wealth of knowledge from all the information both on the forums and on GBA, so thank you for that.

I wanted to get a second opinion on the final insulation for our new construction house.  It’s just as a final confirmation to make sure that I haven’t missed anything.

For reference, we are in Zone 6 (southern Maine).

Sidewalls 2×6 Framing, 16″ OC:
Siding: Ascend Alside (R2)
Exterior Insulation: 2″ XPS, taped.  The 2″ XPS + Ascend R2 is to keep the sheathing warm, to prevent condensation buildup.
Sheathing: Huber ZIP
Interior Insulation:  This is where I’m undecided.  The insulation subcontractor recommends open cell foam for the walls, especially for making the house air tight (we’ll have an ERV).  Our architect was leaning towards mineral wool.  I’m inclined to go with open cell foam.
Interior: Gypsum, painted.

Roof: Hot roof – 8″ closed cell foam, to prevent moisture condensing on the roofing sheathing.  We’re set on this, as we have to use CCF.

Is there any glaring issue that I need to know about regarding insulation type?  Am I fine with the exterior and interior wall setup as described above?  I just want to make sure I’m not missing anything regarding permeability etc.

Thank you