Chimney Breast Removal Merton

Approval under the building regulations comes before the first brick moves, and the inspector wants to see the propping, the beam and its bearings while they are still exposed. Those visits go into the programme. The design comes from a structural engineer we appoint; our job is to build it accurately and make good.

In Merton, removing a breast on one floor typically costs £2,200 to £3,250 on a steel beam, and £3,000 to £5,000 across two floors (indicative London ranges, MyBuilder and Checkatrade, 2026). GS Renovation Ltd, a building contractor based in Potters Bar, does the work in Merton.

How the job runs

1. Free site survey at your Merton address: which floors the breast runs through, a shared stack, any live flue.
2. The engineer we appoint designs the support, and the work is registered with Merton Council building control or an approved inspector. On a shared wall you serve the party wall notice as building owner; we supply the drawings.
3. The floor above is propped and the breast comes down in courses from the top; what remains sits on the support the engineer specified.
4. Building control inspects the support before it is covered. We make good, and the completion certificate follows.

Chimney breast removal in Merton's terraces

Most Merton terraces still carry their original breasts in the two front rooms and often in the closet wing behind. Homeowners usually want the ground or first-floor breast removed to reclaim the alcoves, but the masonry stack continues up through the floors and out at the roof. That retained weight cannot be left hanging, so every removal starts with a structural engineer confirming exactly what is being supported.

Where we take out a breast on the lower floor and keep the stack above, we carry it on a steel beam set on padstones; gallows brackets are used only where the engineer and building control accept them. Where the stack is yours alone and the whole flue is redundant, taking it down and making the roof good can be the better answer, because it removes the load and the future damp risk, but a stack shared with next door usually stays.

Housing in Merton

Around 87,830 homes make up Merton on the valuation list; 42% are flats and 58% houses, and 26% date from before 1919, 37% from between the wars and 36% from after 1945. 43% of homes here are terraced; the breasts of a terrace in Merton usually sit on the party wall back to back with next door's, so removing one needs a party wall notice.

Chimney breast certificates and Merton Park roof slopes

Merton building control issues a completion certificate when the work is finished and advises keeping it because it will be needed to sell the property. That matters for chimney breasts in particular. A removed breast is easy to spot from the loft, or from a stack on the roof with nothing visible beneath it in the rooms, and a buyer's solicitor then asks for the certificate. Keep it with the engineer's calculations and photographs of the steel taken before it was boxed in, so a sale in Merton is not held up while an old removal is investigated.

The roof needs its own check in the John Innes Merton Park conservation area, one of the two Merton conservation areas, with Wilton Crescent, where planning permission is needed for the changes set out in four Article 4 directions. The second John Innes Article 4 (2) direction withdraws permitted development for altering a roof where the roof slope would front a public highway or other public space. Taking a redundant stack down below the roof and retiling the gap alters that roof, so ask Merton Council before the scaffold is booked. Carrying the stack on steel and leaving it standing avoids the question.

Party wall and damp control in SW19

Merton's terraces share a party wall with the house next door, and the chimney stack almost always sits within it. Removing the breast, or bearing a beam into that shared wall, is notifiable under the Party Wall Act, so you, as building owner, serve notice on the adjoining owner before work begins. We give you the drawings and programme the notice needs and keep the neighbour informed throughout the work.

The structural support is notifiable under the Building Regulations, and Merton Council's building control signs it off, not the planning department. Once the stack is secured we cap any redundant flue with proper ventilation so the old brickwork breathes and stays dry, then replaster the wall and reinstate the skirting so there is no sign a breast was ever there.

What the house is like meanwhile

A chimney breast removal is noisy and dusty for a short period rather than mildly disruptive for a long one, which most people find easier to live with. Expect two or three days of breaking out. Through those days the room is out of use and sealed off, and we would suggest not working from home in the room directly above it if your week can be arranged any other way. If you have small children or anyone with a respiratory condition at home, tell us at survey and we will phase the noisy work differently.

The rest is manageable. Water and power stay on. Heating may be off in that one room while a radiator is moved. Dust is caught at source with extraction rather than left to settle, and the route from the room to the front door is boarded and sheeted. In a Wimbledon or Mitcham terrace where the front door opens straight into the hall, we set the screen at the room doorway so the stairs stay clean.

• Hearth removal and floor structure reinstatement
• Ceiling and joist support where the breast carried them
• Programme planned around party wall notice periods for a shared stack

VOA Council Tax stock of properties, March 2025, for all 25 statistical areas in Merton. Counts rounded by the VOA.

When comparing chimney breast removal in Merton with other work, it helps to read home renovation in Merton, our Merton area guide, builders across London, the Party Wall Act for a breast in a shared wall, our London chimney breast removal page and Cracks in Walls: When to Worry.

The GS Renovation Difference in Merton

Merton homeowners choose GS Renovation because we treat chimney breast removal as the structural job it is. You get an engineer-checked support, usually a steel beam on padstones, with gallows brackets only where the engineer and building control accept them, building control handled end to end, tidy working in an occupied home, and a signed-off, replastered finish, backed by our founder's 30+ years on the tools.

Checked by Abdelaaziz Saaid, founder and director of GS Renovation Ltd (Companies House no. 14611254). Structural design is by the consulting engineer appointed to your project.