good morning De!
On surface a wall like this looks like a good idea but in reality I wan to point out only one thing for you to take into consideration as I am one who is considered an expert in coatings and finishes.
Black paint on the exterior of that wall in an 8 inch wide air space with glass exterior.
With super heated air space when sun is exposed on that surface, and sunlight will be magnified by the glass, that black paint is going to fade and weather away. How do you gain access to re-surface it?
Just something to consider before you actually do this. I like the general concept of using mother nature's very own source of heat which is free, but am only concerned about the durability of the paint and how you replace it......
just doing a little thinking before I leave for my first appointment today.
Greetings from Youngstown.....
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