I have a gas fireplace with a chimney that goes up through a second floor space that I'm trying to recoup. I've been told I can put in a ventless fireplace and remove the chimney but the cost for removal, install of the fireplace and possibly redoing the tile around my existing fireplace makes that option seem price-prohibitive. I'm wondering if its possible to reroute the existing chimney through the wall behind this picture which is just unused space. Can a 45/90 degree elbow be used to route the chimney into the wall then back out through the roof? The floor in this room will be a raised floor for a media room so there will be about 10-12" to play with to route the pipe.