I am getting ready to build a new home and I would like to go ahead and have the walls of the home theater room framed out. The theater room is going to be located in the basement and I plan to start on the theater room in a couple of years. Since the walls framing will be permanent I need to get the dimensions correct. I was thinking to make the room 18' X 20' is that a good size or should I do something different? I plan to have a 100" projector for video & audio is going to be high end (Not sure what yet) My budget for the audio & video equipment is $20,000 (not including the rooms construction) so I defiantly want to design the rooms dimensions properly. I would hate to spend that kind of money on the audio system and it not sound its best because of room size. Any suggestions from experienced home theater enthusiast would be greatly appreciated.