I'm renovating a house that is 67 years old. Not in terrible shape, but there are relatively minor issues with the plumbing, wiring, etc. Okay, a new septic system isn't relatively minor, but I'm going to contract that out.
My first question pertains to ducting. I know there is a supply, and there is a return. I also know that a crawlspace has to be insulated and vented in some way shape or fashion. Currently, there is no foundation insulation inside, and no insulation under the floor joists. The only part of my house that is on a crawlspace is an addition to the original house, which has a basement.
There is feed and return ducting going through the crawlspace at this time, along with water lines (supply and waste) for the bathroom, which is the only actual "room" above the crawlspace. Obviously, that's not the most efficient way to heat a house (currently forced air gas heat and room a through-the-wall A/C unit).
If I were to insulate the inside foundation well, would I be able use that space as a "return tank", bringing all the return air into that space, and then ducted to the furnace? This would keep the crawlspace heated to a point (and A/C-ed once I upgrade) and would also allow for the removal of any water that seeps up from the ground. Plus, any ducting and plumbing to the bathroom would go through this moderately conditioned space, too, leading to less heat loss for those runs.
I appreciate the advice and look forward to getting more wisdom in this area.