Might b a stupid question, how close can a chimney pipe b to a natural gas line or gas meter inside and outside of the house? I'm helping me buddy install his wood furnace and we're having some issues running the pipe outside, the furnace is located next to the gas furnace and duct work like the owners manual recommends. Or do we need to put the furnace in another room and run insulated duct work to the existing duct work? We're stumped on what to do.