The Fine Homebuilding editors offer advice about framing new stairs for a deck, choosing the right level for a whole-house construction project, and figuring out how to upgrade an old HVAC system for efficiency and comfort.

Patrick kicks off this week's conversation with an update on his trial of Spray & Forget mold remover to clean up the grungy siding on his house, then Rob contemplates some interesting architectural follies he saw on a local country road. Matt gets us into a more technical topic–one contractor's peculiar way of insulating the underside of a house built on piers–before the crew jumps into answering a few listeners' emails.