In a Mitcham semi the breast and its alcoves swallow the width of a single bed. Take it out on both floors and the bedroom and the front room each gain a usable wall. The stack left above is carried on a steel beam to the structural engineer's calculation, with the flue capped and vented afterwards.
Chimney breasts in Mitcham's period and interwar homes
Many Mitcham houses still carry their original chimney breasts on both the ground and first floors, taking up valuable space in rooms that no longer need an open fire. In the interwar semis and period terraces here, the stack is usually built into the party wall shared with the house next door. Because the breast helps carry the masonry above, we begin every job with a structural engineer establishing precisely what the stack and breast are supporting.
Where you remove a lower breast but keep the stack above, that retained masonry has to be picked up. We support it on steel gallows brackets bolted into the party wall, or on a small beam where brackets are unsuitable for the loading. In many Mitcham houses the whole stack is redundant, so the cleaner solution is to remove it in full, right up through the roof, and make the roof covering good and weathertight.
Party wall and building control in CR4
Because Mitcham's semis and terraces share a party wall with the neighbour, and the chimney stack usually sits within it, removing the breast or fixing gallows brackets affects that shared wall. That makes the work notifiable under the Party Wall Act, so you serve notice on the adjoining owner before starting. A stack is never left unsupported: the retained masonry is always carried on engineered brackets or a beam designed for the exact load above it.
The structural support is notifiable under the Building Regulations, so Merton Council's building control inspects and certifies it, and no planning permission is needed for this internal work. We manage the whole job: the engineer's calculations, safe removal and propping, capping any redundant flue with ventilation to prevent damp, and replastering so there is no trace the breast was ever there.
The stages Merton building control will inspect
Chimney work is inspected, not simply approved on paper. The application goes in with the engineer's proposal before anything is touched, and the first meaningful visit happens when the support is installed but still visible, so the inspector can see the bracket fixings or the beam bearings, what they are fixed into, and how the retained masonry above is packed and pinned. Once it is plastered, that evidence is gone for good. The application itself is straightforward, but it has to be in before the first brick moves rather than afterwards.
There is then a completion inspection covering the capped and vented flue, any making good to the roof, and the finished work generally, followed by the completion certificate. In a CR4 semi we book those visits into the programme at the outset rather than calling at the last minute, because an inspector cannot always attend the next day, and nobody wants a job stopped with the propping still up and the room out of use.
- Ground floor removal with the upper stack fully supported
- Roof tiling, flashing and leadwork made good
- Building control notification and inspection sign-off
- Steel beam support where gallows brackets are unsuitable
- Gallows bracket support for a retained stack above
The GS Renovation Difference in Mitcham
Mitcham homeowners choose GS Renovation because we treat chimney breast removal as the structural job it is. You get an engineer-designed support solution, gallows brackets or beam correctly specified and Merton building control handled end to end, and tidy working in an occupied CR4 home, all backed by more than 30 years across Merton.
- Neighbours spoken to early when the stack is shared
- Roof, flashing and leadwork made good where a stack comes down
- Waste cleared as we go, not left piled in the garden
- Rubble bagged and carried out, not tipped into the room below
- Rated 4.9 from 31 reviews on MyBuilder
- A written scope and programme agreed before work starts