This is an old picture of the origanl gas fire whcih housed the back boler behind. Gas fire and back boiler was removed and replaced with a combi a few years ago. So I've had this set up for a few years. i made the black infill myself, fitted and air vent and also a black single socket which could have powered and electric fire. Socket is hard too see. Won a gas stove a few weeks back and now in the middle of renovating the whole flat. Today I opened up the brickwork. A fireplace shop I visited said an opening of 36" square was OK. Won't be able to achieve this in width, as downstairs maisonette shares the chimney. Used a large disc cutter to cut the bricks down. The brick that have been removed are going to be reinsted tommorw as they were very loose. This is something I am trying to recreate. i like the idea of a a mantel to store ornaments on. Another idea I have is to install a single leaf lintel with a soldier row of bricks, which protrudes past the plaster.