We are having our living room plastered and our existing fireplace rendered. We are in the process of removing the stone cladding around the fireplace to expose the brickwork. Above the fireplace there was a 2in thick stone slab which we removed before realising there are no bricks behind it and now there is a large gap where the likelyhood is that the smoke will release into the room rather than up the flue and out of the chimney.
We removed the stone because the bottom of it came out further than the existing stonework and as the render will not be as thick as the cemented stones (we were going to render iver the big stone in question too which would have made it protrude even further) we didn't want it to look daft.
Posting on my phone so a picture will follow but might take a few minutes.
Any help/advised will be greatly appreciated