I'm finishing part of my basement. It is a 20' X 14' space. The furnace/A/C is in the next room. I know very little about heating. How many registers/returns do i need for this space. What kind/size ducts do i use. Any suggestions would be appreciated.

Currently, my garage dryer has no vent outlet, so all the hot air stays in the garage, which makes it unpleasant and rusts everything up. The garage is on a slab, with the rest of the house having a crawl space. All the exterior wallls of the house are brick, with the dryer back against a drywall/wooden wall on which the other side is the kitchen. I was planning on putting a small slab of cement under the dryer, which would raise it up so that its outlet vent would line up with a 2x6 wood piece that goes to under the house, from under the house it would take a 90° turn and head to the brick exterior wall about 8 feet away. The problem with this would be drilling into the brick wall or the foundation (depending on where it would line up under the house; I may not be able to get high enough for just brick). Would drilling a 4" hole through the bricks or foundation do anything to the stability of the house? And as for just letting it vent under the house? I am reluctant to do that for mold and excess moisture reasons. I dont think all that moist hot air would be good for the wood either.