Crawlspace insulation and encapsulation: what if there's no sill plate?
I'm insulating and encapsulating a crawlspace built of concrete blocks. There is no sill plate. Yes, it needs a sill plate, but I will not be putting one in. Best practice is to insulate the walls and the space between the joists with XPS board before attaching the vapor barrier, but at the moment, because there's no sill plate I can put my hand into the centers of the blocks. So it will basically be a chimney to bring in vapors and moisture if I don't cap them off. What is the right way to do this?