Share 'Distribution from wall furnace for small apartments'

OK, folks -- time for some creative thinking about a 16-unit building we are trying to weatherize in SE Wisconsin. It's two stories arond a central courtyard, with most units accessed by a door direct to outside. (That is, most units have either two or three walls exposed to ambient, with a wall that's about R-6. We won't be able to touch the walls, but the attics/secondfloor ceiling will go to R…