Projects

Removing a chimney breast on a party wall

In most South London terraces the chimney breasts sit on the party wall and share a stack with next door. Taking one out is party wall work.

Section 2 notice
2 months' notice
Engineer's design needed

Why it is party wall work

A chimney breast built onto a party wall is part of that wall. The Act lists cutting away a projecting chimney breast as work to a party structure under section 2, so your neighbour needs at least two months' written notice.

A chimney breast on a brick party wall in a loft, with new floor joists being laid beside it — A chimney breast on the party wall in a Balham loft, with new floor joists going in beside it.

Supporting what is left

When a breast comes out on the ground floor but stays upstairs, or the stack stays on the roof, the masonry above needs proper support. That normally means a steel beam designed by a structural engineer and approved by building control. The award will refer to that design.

Next door's side

Flues. A shared stack may still carry flues from next door's fireplaces or boiler. Those have to stay intact and working.
Stability. The stack belongs to both houses. Removing support on one side affects both.
Noise and dust. Breaking out a breast is loud and dusty work right against the neighbour's rooms. The award can set working hours and protection.

Taking down the stack

Removing your half of a shared stack above the roof is a bigger job. It needs a design that leaves next door's half stable and weathertight, and it is far easier with your neighbour on board from the start.

Questions people ask

Can I take out my chimney breast if next door has kept theirs?

Generally yes, with proper support for what is left above, notice under the Act and, if your neighbour dissents, an award setting out how it is done.

Does removing a chimney breast need building regulations approval?

Yes. It is structural work, so building control has to approve it. That is a separate process from the party wall notice.

What about the shared chimney stack?

If the stack stays, it must be properly supported. If you want to take down your half of the stack, that affects your neighbour's half too, and it needs careful detailing and their involvement.