Modifying a chimney breast structure

[Calvin]

Hi all, I've tried googling but I obviously haven't found the right keywords yet :- )

I want to increase the size of the "builder's opening" in my chimney breast by removing a half-brick column from each side. Obviously the brick colum n each side supports the load of the bricks above and ideally I'd like to d o the calculations to show that it's safe. But where to start?

At floor level the chimney breast is 40cm brick, 60cm opening, 40cm brick a nd I want to end up with 30cm brick, 80cm opening, 30cm brick.

Don't worry about the effect on the lintel bearing by the way as a previous owner removed it! Part of the job will be to reinstate it but obviously w ider and bearing on the new reduced size structure.

Can anyone help?

[newshound]

Assuming it is a normal sort of property with a two story chimney then

30 cm either side sounds OK to me, with suitable overlap for the lintel. The loads can't be that high or you would see signs of cracking above after removal of the lintel.

[JimK]

Goggle "Self corbelling"

Mornington crescent....

Jim K