My father is attempting to add another room in our basement back home, roughly 4 hours away from me (wood framing only). He wants to heat this new room, obviously but isn't sure of the best way to do it. There is a heat duct that runs right outside one of the interior separation walls that he's going to tap into and run heat from. This room won't be used all the time so it's not necessary to heat it at all times - meaning he wants to be able to shut off the heat source to that room when he can. Does anyone have any ideas? He used to be a carpenter so he's well informed about how to build the room itself he just doesn't have much experience in heating or adding a new heat duct. Any ideas or advice will be appreciated, thank you!