Brick arch in chimney breast

Joined
11 Jan 2013
Messages
6,901
Reaction score
1,635
Location
Durham
Country
United Kingdom
Disappointingly, the arch in the chimney breast has been removed/bricked up by others when installing a rather nasty fireplace.
I fancy reinstating it- main question is whether the metal strap usually supporting such arches is steel or wrought iron. Yes I could just put a lintel in (be a 3kw woodburner going in eventually) but it won't look as pretty.
 
Sponsored Links
The metal bands are needed because usually the brickwork pillars at each side are only 1 brick thick. This doesn't provide enough mass to resist the thrust of an arch, so the metal band acts to hold the arch together. (https://www.idostuff.co.uk/sections/DIY/Chimney Arch/Brick_Arch_self-corbeling.html)

These would be wrought iron but you'd be hard pressed to find modern wrought iron (what is usually sold as wrought is actually just mild steel but worked on by a smith).

However... I'd personally pay a bit more and get an arched steel lintel fabricated. http://www.harvey-steel-lintels.co.uk/archlintels.htm

The arch tie approach isn't really used anymore - beam lintels are more robust.
 
How about re-instating an arch using a plywood former/frame?
No need for a lintel then.
Thought about that, slight paranoia about Edwardian builders must have had a reason for putting those straps in on the fireplace.
 
Sponsored Links
The metal bands are needed because usually the brickwork pillars at each side are only 1 brick thick. This doesn't provide enough mass to resist the thrust of an arch, so the metal band acts to hold the arch together. (https://www.idostuff.co.uk/sections/DIY/Chimney Arch/Brick_Arch_self-corbeling.html)

These would be wrought iron but you'd be hard pressed to find modern wrought iron (what is usually sold as wrought is actually just mild steel but worked on by a smith).

However... I'd personally pay a bit more and get an arched steel lintel fabricated. http://www.harvey-steel-lintels.co.uk/archlintels.htm

The arch tie approach isn't really used anymore - beam lintels are more robust.
Ahh, good point. Not got that far into the breast yet so don't know. Ta for the links.
 
The metal bands are needed because usually the brickwork pillars at each side are only 1 brick thick. This doesn't provide enough mass to resist the thrust of an arch, so the metal band acts to hold the arch together. (https://www.idostuff.co.uk/sections/DIY/Chimney Arch/Brick_Arch_self-corbeling.html)

These would be wrought iron but you'd be hard pressed to find modern wrought iron (what is usually sold as wrought is actually just mild steel but worked on by a smith).

However... I'd personally pay a bit more and get an arched steel lintel fabricated. http://www.harvey-steel-lintels.co.uk/archlintels.htm

The arch tie approach isn't really used anymore - beam lintels are more robust.
Interesting, I would have thought that the downward load acting on the brick pillars, taking into account half all the load of the full chimney breast above it ( except for the inner section of corbelled brickwork) would have been more than enough to counter the overturning horizontal force exerted by the bricks contained in the corbelled section and even more so as the sides of the chimney breast would be keyed into the adjacent wall, although the shear forces within the mortared bricks and the actual dimensions of the opening would be further factors for consideration. A quick easy former seems to be the most logical reason.
 
Interesting, I would have thought that the downward load acting on the brick pillars, taking into account half all the load of the full chimney breast above it ( except for the inner section of corbelled brickwork) would have been more than enough to counter the overturning horizontal force exerted by the bricks contained in the corbelled section and even more so as the sides of the chimney breast would be keyed into the adjacent wall, although the shear forces within the mortared bricks and the actual dimensions of the opening would be further factors for consideration. A quick easy former seems to be the most logical reason.
From other brickwork in this place I wouldn't put money on the sides being keyed in!
 
Put a single leaf steel lintel or angle iron a bit higher up to carry the load then build your "cosmetic" arch underneath. Those arch lintels aren't cheap.
 
Interesting, I would have thought that the downward load acting on the brick pillars, taking into account half all the load of the full chimney breast above it ( except for the inner section of corbelled brickwork) would have been more than enough to counter the overturning horizontal force exerted by the bricks contained in the corbelled section and even more so as the sides of the chimney breast would be keyed into the adjacent wall, although the shear forces within the mortared bricks and the actual dimensions of the opening would be further factors for consideration. A quick easy former seems to be the most logical reason.
The arches tend to be shallow which makes the horizontal component larger.

You can try it but I wouldn't bet my safety on 9" of masonry resisting much lateral load of anything.
 
The arches tend to be shallow which makes the horizontal component larger.

You can try it but I wouldn't bet my safety on 9" of masonry resisting much lateral load of anything.
Yes, I guess it whether a lateral force of 1/2 the weight of the corbelled brick section (max it could be) would push the pillar over?
 
Put a single leaf steel lintel or angle iron a bit higher up to carry the load then build your "cosmetic" arch underneath. Those arch lintels aren't cheap.
That's sounding like a winner- will come back once I've pulled the nasty fireplace out the way & let you all know what I find.
 

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.


Are you a trade or supplier? You can create your listing free at DIYnot Local

 
Sponsored Links
Back
Top