I’m planning a full retaining walkout basement on one side of a home, and I’m dealing with a tricky detail where the basement retaining wall extends outside the building envelope to create the walkout exit. The major constraint here is that we really want the insulation on that basement wall to be fully exterior to both keep the thermal mass inside the building and to also have a nice tile-ready interior concrete wall.

My question is what’s the best way to provide a thermal break in this system. The only thing I have thought of is to completely disconnect the retaining wall portion (non-basement) and connect it with exposed rebar surrounded by insulation to the basement wall. But honestly, that seems like a last resort, probably not the best option, and would require building two separate walls.