Reconstructing original fireplace opening

2 Aug 2023
Reaction score
United Kingdom
Hello all,

I would love a couple of pointers please ‍(y)

I live in a 1980’s built house with an external chuted brick/block built fireplace. It has already had one modification done to it prior to me moving in, the original was a floor to lintel opening - using a redbank lintel (I excavated part of this in the backfill in the builders opening) The last re iteration was an art deco style wall mounted inset gas fire, in which they had to remove part of the block to get the inset to fit right. I have posted a pic of the last fire that was in there and the current opening once I have removed the fire and the fireback.

My ultimate aim is to have a multifuel chimney fitted, but I’d like to do most of the prep and building work myself.

The questions I have are :
1) The blockwork that was smashed out either side of the fire opening to allow the inset fire has exposed the cavity to the outer skin, I need to brick this back up to make a proper opening, but do I need to knit the blockwork back together, ie take more out to tooth out the blocks and lay fresh full ones so they tie themselves in or can I just block the sides up without toothing out?

2) the old redbank lintel / gathey I presume was partly removed and replaced with a metal mantle on the inside skin, however the aparture part of the original gather that is still part of the chimney stack is still at the top. It was a bit of a hack job to fit a fireback and black diamond damper for the gas fire into the space made and I’m wondering can this be made to look pretty with a bit of gringing and morter work / painting? now that I have exposed the original gather.

3) the rubble underneath goes well bellow floor level, I’ve exposed the gas feed to cap off & make safe, will I then be able to backfill rubble @ put a concrete base in to floor level to support the new Fireplace & hearth?

Many thanks for reading and any clues would be greatly welcomed!

Pics attached,



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