Remove Chimney breast and keep the stack as semidetached house. Need advise

[Jonny Vee]

Wife is pushing me to remove chimney breast to simplify kitchen layout and get more room.

We also have another chimney on the living room which has been converted to gas and don`t see the pont how having these massive walls.

My idea is to remove both breast and get more room on both floor and use gallows bracket. The layout is like an upside down Y.

Haw anyone remove it. Do I need to contact building control and structure engineer dispite not touching any structure wall?

I can easily buy some gallows bracket off shells and they seem strong enough to support the weight as this would be minimal considering I only wanna leave the last part of the stack just inside the house.

Could you also advise if I have to maintain ventilation.

Thanks

 

[JP_]

I had a builder remove mine. All chimney removed from top to bottom, including the hearth (which was another cause of damp judging by the increased woodworm activity all around it).
Unless you're very competent and have bundles of energy and some good tools, I'd get the pros in. My 2 builders worked hard taking my old chimneys out, and there was an unbelievably large pile of bricks and a shed load of dust.

Amazing how much more space we created though.

 

[Mottie]

When we moved into this house in 1990, we had a floor mounted, room ventilated gas boiler in the kitchen. It was 30 years old and on its last legs so after a couple of years we fitted a new boiler but sited it in the loft. The chimney stack was removed from the kitchen to make it bigger which just left the remainder of the chimney going up the landing, through the loft and out of the roof. We just left it hanging and used the stack to get the feed and return to the boiler plus the gas pipe up to the loft to the new boiler. Eventually we removed the rest of the stack from the loft and roof when we had the roof removed to re-felt it. All that remains is the middle chimney section on our landing - can’t remove that without Ré-routing the boiler feed and return plus the gas feed. Never bracketed it, never got in touch with building control, just left it hanging there. Been good for 27 years!

 

[IT Minion]

Building control will want to be involved as you're going to have the top part of the chimney supported by those gallows brackets.

I just had my chimney removed from my roof but left the breasts in for now, Building control wasn't worried about most of it as there was no heavy brickwork hanging about, but they insisted that I brick up the old fireplace to ensure no one tries to use it and burn the house down.

You should ventilate the remaining chimney, top and bottom I think.

 

[Leofric]

Do I need to contact building control and structure engineer dispite not touching any structure wall?

Why do you think you are not touching a structural wall You need Building control and structural involvement for structural alterations which your proposals are.

I can easily buy some gallows bracket off shells and they seem strong enough to support the weight as this would be minimal considering I only wanna leave the last part of the stack just inside the house.

I wouldn't consider the weight of brick chimney stacks as minimal.
ps is the stack on a party wall

 

[paulrockliffe]

Lots of BCs don't like gallows brackets at all because they rely on the lateral strength of the wall to deal with the horizontal forces they impose. It's not easy for a structural engineer to assess whether an old wall is strong enough in the plane it was never designed to take any load in.

 

[bobasd]

its not clear to me exactly what you propose to remove:
do you intend to remove all chimney breasts up to the loft - and then leave the flue gatherings in the loft (the Y) and the stack on the roof to be supported by brackets or lintels?

there are national Regs and local Council requirements to deal with - there's also the possibility of the PWA (The Party Wall Act) coming into play.
for example, do you know what condition any neighbour's c/breast's are in or are they even there?
for example, some c/breasts act as structural buttresses & cannot be removed.

best and safest practice is to talk with BCO, and then get an expert on site.

fwiw: as previously mentioned on this site and in other places - its best to leave chimney stacks in place because they are seen to be appropriate for the property.

 

[Leofric]

So what are you going to do Gio Russ

 

[Jonny Vee]

its not clear to me exactly what you propose to remove:
do you intend to remove all chimney breasts up to the loft - and then leave the flue gatherings in the loft (the Y) and the stack on the roof to be supported by brackets or lintels?

there are national Regs and local Council requirements to deal with - there's also the possibility of the PWA (The Party Wall Act) coming into play.
for example, do you know what condition any neighbor's c/breast's are in or are they even there?
for example, some c/breasts act as structural buttresses & cannot be removed.

best and safest practice is to talk with BCO, and then get an expert on-site.

fwiw: as previously mentioned on this site and in other places - its best to leave chimney stacks in place because they are seen to be appropriate for the property.

I'm going to remove chimney breast and leave the stuck outside the roof. My idea is to leave the stuck 1 meter below the roof.

The problem I found today when I made a survey is that the party wall has an extra layer of the blue block looking like a thermo block.

What is very strange is that the brick wall between the 2 breasts is 280mm and bricks are visible. on the left Breast, I can only see the blue block and the projection from that is already 300mm. On the right breast has a projection of 450mm from the blue block.

Building control has asked for drawings and advised to use standard details but I don't understand where is and if there is the brick wall behind the blocks.

 

[^woody^]

That's one hell of a shared stack with non standard loading from the blockwork and neighbour's flues.

Party Wall Act wil apply and make sure it's an experienced structural engineer who knows about flues as well as structures.

I doubt gallows brackets will be acceptable for that.

 

[bernardgreen]

Do I need to contact building control and structure engineer dispite not touching any structure wall?

The part of the stack you intend to remove is structural, it supports the heavy weight of the stack above it.

I can easily buy some gallows bracket off shells and they seem strong enough to support the weight

You can buy them easily, but can you fit them as easily, how will you support the top section of the stack beween the time you have removed the bottom section and the time you have got the brackets fitted to the wall. It takes less than a few seconds for an un-supported stack to collapse.

 

[Newboy]

I would guess that you have a Victorian semi/terraced house. What would have been an open loftspace across the two properties has had a block wall added on top of the party wall to separate the two properties. The blockwork is adding load onto the stack rather than providing any support. The stacks are disproportionately large and probably contain four flues in each stack (2 from your property and two from your neighbours).

You have no chance of using gallows brackets and you're going to need a party wall agreement and a good structural engineer.

 

[bobasd]

OP,
you should stop your project right now.
besides the objections mentioned above there are further structural & Regs difficulties that you might encounter.
you should best leave all your chimney breasts alone.

 

[johnny2007]

I second bobasd view.
You're in dangerous ground removing that monster.
Your neighbour would be able to charge you for plaster cracks for the next decade IF (BIG IF) all goes well.
Those chimneys were built as integral part of the houses, removing them is always a risk even with best engineers involved.
Leave it alone and make your open fires the central features of your home.

 

[IT Minion]

A flat removal may not be practical (most things are possible if you blow enough money on them), but would leaving the sides and just chopping out the front be less risky and more achievable? That leaves you with a cavity that can be used as built in storage but, as a completely unqualified amateur, seems like it might still be able to provide the structural strength?

Something to discuss with the Structural engineer perhaps.