I have taken off a horrible fire mantel and due to the cost of gas wish to replace the original gas coal effect fire with a real fire place for wood and coal. I have have had the gas disconected and bought a new wooden mantel.
My problems are that
1. the old marble surround is now too big for the new mantel and will need cutting. Should I be doing this to the inside measurements of the new mantel, and if so is it held to the wall with just the cement behind or is there another way?
2. When I took the faulse clay fire back out to have the chimney cleaned, it was obvious that there used to be a boiler there at one time and the space is quite large and full of uneven and slightly dodgy brickwork. One or two seem potentially quite loose if fiddled with, I have been told to infill this space with a substance called 'melicalight'? I have googled this but can't find it. How should I go about infilling this gap and will it also allow me to fill the gap which would otherwise allow soot to fall back behind the fire back?