Chimney Breast Removal · London

Chimney Breast Removal, Done Safely

Reclaiming the floor and wall space a chimney breast steals — on the ground floor, the first floor or full height — with the masonry above properly supported on gallows brackets or an engineered steel beam, the structure signed off by Building Control and the Party Wall process handled for you. Designed by our in-house structural engineers and built by our own trades under one fixed-price contract.

A Single Fixed-Price Contract
Engineered, approved and built in-house
Structural surveyIncluded
Engineer's calculationsIncluded
Gallows brackets / steelIncluded
Building control sign-offIncluded
Party wall noticesHandled
Aftercare warranty10 years
103+
Completed Projects
RIBA
Architect Partners
MIStructE
Structural Engineers
Gallows
Brackets & Steel
Building
Control
Compliance Support
Party
Wall
Notices & Awards
£10M
Fully Insured
RICS
Chartered Surveyors
£2.5k£9k
Single Floor to
Full-Height Removal
13
Programme Weeks
By Scope
Engineered
Support & Sign-Off
100%
Fixed-Price
No Hidden Cost-Plus

The Wall Back, the Breast Gone

A chimney breast eats into a room — a metre-deep block of redundant masonry, usually housing a fireplace no one lights any more, taking floor space, dictating where furniture goes and breaking up the wall. Removing it is one of the highest-value small projects in a London house: it squares off the room, frees a useful run of wall, and often makes the difference between a bedroom that fits a proper wardrobe and one that does not.

But a chimney breast is structural, and that is where it has to be done correctly. Whatever you leave behind — the breast on the floor above, the stack on the roof, or your neighbour's flue sharing the same party wall — has to be carried by something. This page is for doing exactly that: chimney breast removal on the ground floor, the first floor or full height, engineered properly, signed off by Building Control, with the Party Wall process handled.

The two ways the masonry above is supported are gallows brackets — steel brackets bolted into a sound party wall — or, more robustly and more often, a steel beam spanning the opening. Which is appropriate depends on the load, the condition of the wall and what Building Control will accept; our in-house structural engineers specify it rather than leaving it to chance. An unsupported or poorly supported chimney breast is one of the most common defects flagged in home-buyer surveys, and it can derail a future sale — so the completion certificate we provide matters as much as the finished wall.

Chimney breast removal is frequently done alongside a knock-through or as part of opening up a ground floor, and we coordinate the two under one programme. For the broader structural capability behind this work, see structural works.

Six Chimney Breast Removal Scenarios

What you remove — and what is left to support — defines the engineering. These are the six situations we handle most.

Most Common

Ground-Floor Only

The breast removed in the ground-floor room, with the breast and stack above retained and supported on gallows brackets or a steel beam. Reclaims the most-used living space — and the scenario that most needs proper engineering for what is left above.

Support neededYes — above
Typical cost£3k–£5k
Programme1–2 weeks
Bedroom Space

First-Floor Only

The breast removed in an upstairs bedroom while keeping the ground-floor fireplace below. The breast above (in the loft) and the stack are supported. A favourite where a bedroom is just too tight for a wardrobe along the chimney wall.

Support neededYes — above
Typical cost£2.5k–£4.5k
Programme1–2 weeks
Cleanest Result

Full-Height Removal

The whole breast removed through every floor, with the stack taken down to roof level and the roof made good. No retained masonry to support internally — structurally the simplest outcome — but a bigger job involving scaffold and roof works.

Support neededNone retained
Typical cost£5k–£9k
Programme2–3 weeks
Both Living Floors

Ground & First Floor

The breast removed on both main floors, retaining only the loft breast and stack on supports. Reclaims space in two rooms at once — efficient, since the scaffold, propping and Party Wall process are shared across one project.

Support neededLoft breast above
Typical cost£4.5k–£7.5k
Programme2–3 weeks
Combined

Breast + Knock-Through

Removing the chimney breast and the dividing wall together to fully open a reception room. Both are structural and both need their own support and sign-off; doing them in one go is tidy and efficient. See our knock-through page for the wall side.

Support neededBeam + brackets
Typical cost£12k–£24k
Programme3–5 weeks
Keep the Fireplace

Breast Out, Stack & Flue Retained

Where you want to keep a working fireplace or the external stack — common on Listed and Conservation Area homes — the breast is slimmed or removed in one room while the flue and stack are retained, supported and weatherproofed. A specialist, heritage-aware approach.

Support neededFlue & stack
Typical costProject-specific
Programme2–3 weeks

What Chimney Breast Removal Actually Includes

Removing a chimney breast safely is a careful structural sequence. Every element below is delivered and warranted under one fixed-price agreement.

Structural Survey

We assess the breast, what it carries, the condition of the party wall and what must be supported once it is gone — the basis for choosing gallows brackets or a beam, and for an honest price.

Engineer's Calculations

Our MIStructE engineers design the support method, size the brackets or beam, check the party wall masonry and produce the calculations for Building Control — the legally required structural design, kept on record.

Gallows Brackets

Where the wall is sound and the load suits, galvanised steel gallows brackets are bolted into the party wall to carry the retained breast above — installed precisely to the engineer's detail, with the Party Wall consent in place.

Steel Beam Support

More often, a steel beam spans the opening to carry the masonry above — stronger than brackets, not reliant on the neighbour's wall alone, and frequently the method Building Control prefers. Sized, seated on padstones and levelled.

Propping & Removal

The structure temporarily propped, the breast removed in controlled sections from the top down, debris managed cleanly, and the support installed before the props come out — the sequence that keeps the work safe.

Making Good

The wall reinstated where the breast was, the floor made good across the reclaimed area, the ceiling repaired, and the recess squared off — so you are left with a flat, usable wall and no trace of the breast.

Flue & Stack

Redundant flues capped and ventilated to prevent damp; the stack taken down and the roof made good on a full-height removal, or supported and weatherproofed where retained. Any gas connection safely capped by a Gas Safe engineer.

Hearth & Fireplace

Redundant hearths lifted and made good, retained fireplaces protected and left fully functional, and the room left ready for the floor finish — no awkward raised hearth where the fire used to be.

Services Re-Routing

Any pipework, radiators, sockets or aerials on or around the breast re-planned and re-routed cleanly into the reclaimed wall — so the new flat wall is usable from day one.

Building Control

Full Building Regulations submission for the structural support, with the work inspected before it is concealed and a completion certificate issued — the document a future buyer's surveyor will look for.

Party Wall

Because chimney breasts usually sit on the shared wall, we serve the Party Wall notices, prepare the schedule of condition and agree the award through our sister surveying company — the step most often overlooked.

Decoration & Aftercare

Plastering and full decoration so the reclaimed wall matches the room, a two-stage snag, a 12-month defects period and a 10-year workmanship warranty.

Carrying What's Left Above

The whole job turns on supporting whatever the removal leaves above. Here are the six things our engineers resolve before the breast comes out.

i.

What Remains Above

We establish exactly what sits above the part you are removing — the upper breast, the loft breast, the stack — and its weight, because that load defines the support. Guesswork here is how chimney breasts end up dangerously unsupported.

ii.

Gallows Brackets

Steel brackets bolted into a sound party wall can carry a retained breast where the load is modest and the wall and mortar are good — subject to the neighbour's consent under the Party Wall process. Economical, but only where appropriate.

iii.

Steel Beam

More commonly we span the opening with a calculated steel beam carrying the masonry above. Stronger, not dependent on the neighbour's wall alone, and often the only method Building Control will accept — our default where the load warrants it.

iv.

Party Wall Condition

The shared wall the breast sits on may also carry the neighbour's flue. We assess its condition and coordinate with the Party Wall process so the support is fixed correctly and lawfully.

v.

The Stack on the Roof

On a partial removal the roof stack stays and must be carried all the way down; on a full removal it comes off and the roof is made good. Either way the stack — and any shared flue — is dealt with deliberately, not ignored.

vi.

The Sign-Off That Protects You

An unsupported chimney breast is a classic home-buyer-survey red flag that stalls sales. The engineered support and the Building Control completion certificate we provide are what give you, your insurer and a future buyer confidence.

Eight Stages, From Brief to Handover

Even a single-room removal benefits from a disciplined, properly sequenced approach. Here is how we run it.

0
Stage 0 · Strategic Definition

Brief & Free Consultation

We look at the breast you want gone, discuss whether you are keeping any fireplace, and talk realistic budgets. No charge, no obligation.

Week 0 · Free consultation
1
Stage 1 · Survey

Structural Assessment

A survey establishing what the breast carries, the party wall condition and what must be supported — the basis for the support method and a firm price.

Within 1–2 weeks
2
Stage 2 · Design

Support Method & Detail

The engineer determines gallows brackets or a steel beam, and we show you the impact on the room, the flue and any retained fireplace before you commit.

1–2 weeks
3
Stage 3 · Engineering

Structural Calculations

Calculations for the brackets or beam and their fixings, produced by our MIStructE engineers, ready for Building Control.

1 week
4
Stage 4 · Approvals

Building Control & Party Wall

Building Regulations submission, and Party Wall notices served on the affected neighbour with the award agreed before work begins.

2–6 weeks (varies)
5
Stage 5 · Construction

Propping, Support & Removal

Structure propped, support installed, breast removed from the top down, stack dealt with, opening made good. Building Control inspects the support.

1–3 weeks on site
6
Stage 6 · Handover

Making Good & Decoration

Plastering, services re-routing, floor and ceiling repair and decoration to match the room, then a snagging walk and the completion certificate.

1 week
7
Stage 7 · Aftercare

Defects Period & Warranty

A 12-month defects rectification period, a six-month service visit and a 10-year workmanship warranty.

12 months + 10-year warranty

Four Tiers, Honestly Drawn

A chimney breast removal can be a plain reinstated wall or a beautifully finished one. Here is how our four tiers differ.

Element
HeritageStandard
ConsideredHigh-End
ConnoisseurPremium
AtelierSuper-Prime
Support method
Gallows brackets where suitable
Steel beam, boxed
Steel beam, flush detail
Steel beam, fully concealed
Wall finish
Plastered, ready to paint
Crisp plaster, level wall
Skim to a high finish
Premium plaster, feature-ready
Floor reinstatement
Made good, threshold trim
Matched flooring across recess
Continuous flooring, levelled
Seamless premium finish
Services
Capped & made safe
Re-routed cleanly
Concealed, considered positions
Full re-plan, integrated
Fireplace / flue
Capped & vented
Neatly finished or retained
Retained feature, restored
Restored chimneypiece, bespoke
Decoration
Dulux Trade, three-coat
Farrow & Ball, four coats
Premium paints, five-coat sanded
Specialist finishes, hand-applied
Indicative (single floor)
£2.5k–£3.5k
£3.5k–£5k
£5k–£7k
£7k–£10k+

Where Your Budget Actually Goes

For a representative single-floor chimney breast removal at around £4,000, here is the honest breakdown of where every pound is spent.

Support (brackets / steel)
18%
Propping & removal
22%
Making good & plastering
20%
Flue, hearth & floor
10%
Services re-routing
7%
Decoration
8%
Structural design & calcs
7%
Building control & party wall
6%
Preliminaries (protection, skips)
2%

The Engineering Behind the Support

Chimney breast removal is structural engineering first. Here is what is calculated and installed.

Support Design

  • Gallows brackets: Galvanised mild-steel brackets bolted to the party wall, designed to BS EN 1993, used only where the wall and load suit
  • Steel beam: Universal beam sized to the masonry load above, on calculated padstones — the more robust and more commonly accepted method
  • Masonry check: The party wall and bearings assessed for condition and capacity before fixings or beams are installed
  • Connections: Resin-anchored or through-bolted fixings to the engineer's specification

Temporary Works & Removal

  • Propping: Acrow props and strongboys sized to carry the breast and anything above during removal
  • Sequence: Breast removed top-down in controlled sections, support installed before props are struck
  • Protection: Floors and adjacent rooms protected, dust screening and managed debris removal
  • Method: Method statement and risk assessment for the removal and any working at height

Approvals

  • Building Control: Full Plans submission with the structural calculations to LABC or an Approved Inspector
  • Inspection: Support inspected before concealment; completion certificate issued
  • Party Wall: Notices, schedule of condition and award by RICS surveyor — almost always required for a chimney breast
  • Gas: Any gas fire connection capped and certified by a Gas Safe registered engineer

Flue, Stack & Making Good

  • Capping: Redundant flues capped with a ventilated cowl and vented internally to prevent condensation and damp
  • Stack: Taken down and roof made good on full removal; supported and weathered where retained
  • Wall: Recess built out flush, plastered and decorated to match the room
  • Floor: Hearth removed, floor made good and the finish run across the reclaimed area
A chimney breast is heavy, and gravity is patient. Remove it without supporting what is left above and the problem does not show today — it shows in the cracks, and in the surveyor's report when you come to sell.
— Hampstead Renovations · Studio Statement

Building Regulations & Party Wall for Chimney Breasts

Removing a chimney breast is rarely a planning matter — but it is always a Building Regulations one, and very often a Party Wall one too.

Removing an internal chimney breast does not normally need planning permission, because it does not change the outside of the house. The exception is taking down the chimney stack on the roof, which alters the elevation and can require permission — particularly in a Conservation Area — or Listed Building Consent on a Listed property. The internal structural work, however, always requires Building Regulations approval, because supporting the retained masonry safely is exactly what the Regulations exist to control. The completion certificate that follows is also what a future buyer's surveyor will ask to see.

The Party Wall etc. Act 1996 very often applies, because chimney breasts typically sit on the wall shared with the attached neighbour — and that neighbour frequently has their own breast or flue backing onto yours. Cutting into the shared wall, or fixing gallows brackets to it, triggers the Act. Notice must be served, a schedule of condition prepared and an award agreed before work starts. This is the step most commonly skipped, and the one most likely to cause a dispute if it is.

We confirm exactly what your removal needs at survey and manage every approval — Building Control, Party Wall, and any planning or Listed Building Consent for stack works — through our in-house team and sister surveying company. For an early budget, use the cost calculator; if you are also taking out a wall, see knock-through.

A Single-Floor Removal, Week by Week

A representative programme for a ground-floor chimney breast removal with a steel beam supporting the breast above. Yours will differ by scope, but this is what a properly run removal looks like.

Week
Phase
Activity on Site
Pre
Design & Approvals
Survey, structural calculations, Building Control submission and Party Wall award completed before site starts.
01
Set-Up & Propping
Room and floor protection, dust screening, engineered temporary propping installed to carry the breast above.
01
Support & Removal
Gallows brackets fixed or steel beam installed and seated, breast removed in controlled sections, props struck. Building Control inspection.
02
Making Good
Recess built out flush, flue capped and vented, hearth removed, floor and ceiling made good, services re-routed.
02
Plaster
Plastering to the reinstated wall and affected ceiling, drying time before decoration.
02–03
Decoration & Handover
Full decoration to match the room, snag list resolved, clean, completion certificate, handover.

What Sets Our Chimney Work Apart

This is a job many do cheaply and wrongly. Here is what makes ours safe, certified and worth the difference.

i

Engineer In-House

Our own MIStructE engineers design the support — brackets or beam — rather than leaving a structural decision to a general builder's judgement.

ii

Always Supported & Signed Off

We never remove a breast without engineering the support and obtaining Building Control sign-off — the opposite of the unsupported removals surveys flag every week.

iii

Party Wall Handled

Because the breast is usually on a shared wall, we manage the Party Wall notices and award through our sister surveying company — the step most often missed.

iv

Single Fixed Price

One agreement covering survey, design, support, approvals and finishes. No cost-plus surprises once the wall is open.

v

Clean Making-Good

We leave a flat, usable wall that matches the room — not a lumpy patch where the breast used to be.

vi

Heritage-Aware

Experience retaining and restoring period chimneypieces and stacks where you want to keep the character, including on Listed homes.

vii

£10M Insurance

Professional indemnity and public liability at £10M, well above industry standard.

viii

10-Year Warranty

An insurance-backed workmanship warranty protecting the structural work long after completion.

Explore Related Structural & Room Work

Chimney breast removal often sits within a wider project. Start here, or speak to us about combining it under one contract.

Structural & Reconfiguration Proof

Comparable projects with real structural work and finishing standards. Browse the case-study hub, and for survey-led due diligence before you commit, see surveying support.

Detailed Answers to the Questions That Matter

What is chimney breast removal, and is it structural work?

A chimney breast is the projecting masonry that houses the fireplace and flue, running up through the floors. Removing it reclaims useful floor and wall space in the rooms it intrudes into. It is always structural work: the breast is heavy, and whatever sits above the part you remove — the upper breast, the stack on the roof, or the neighbour's flue — must be properly supported. That means a structural design, the right support, and Building Control sign-off. We handle all of it under one fixed-price contract.

Can I remove just the ground-floor chimney breast and leave the rest?

Yes, and it is one of the most common requests — but it is precisely the case that needs careful engineering. If you remove the breast on the ground floor, the breast and stack above still need to be carried. This is done with gallows brackets bolted to the party wall (where the wall and mortar are sound) or, more often and more robustly, a steel beam supporting the masonry above. A full-height removal avoids this but is a bigger job. We advise which approach suits your house at survey.

How is the chimney breast above supported once the lower part is removed?

Two methods. Gallows brackets — steel brackets bolted into the party wall — can support a retained breast above where the wall is sound and the load is modest, and where the neighbour's consent and the Party Wall process allow. More commonly we use a steel beam spanning the opening to carry the masonry above, which is stronger, does not rely solely on the neighbour's wall, and is often the only method Building Control will accept. Our engineers specify the right one for your situation.

How much does chimney breast removal cost in London?

As a guide: removing a chimney breast on a single floor with making-good typically runs £2,500–£5,000; a full-height removal through the house (including roof works to the stack) £5,000–£9,000; and combined with other structural work such as a knock-through, more. Price depends on the support method, access, the stack and how much making-good and decoration is involved. Use the cost calculator for an early band, then we confirm at survey.

Do I need planning permission to remove a chimney breast?

Removing an internal chimney breast does not normally require planning permission, as it does not change the external appearance — unless you also remove the chimney stack on the roof, which can affect the elevation and may need permission, particularly in a Conservation Area, or Listed Building Consent on a Listed property. It always requires Building Regulations approval for the structural support. We confirm the position for your property at survey.

Do I need Building Regulations approval and a structural engineer?

Yes to both. Chimney breast removal is structural, so a structural engineer must design the support (gallows brackets or beam) and Building Control must approve it and inspect the work before it is concealed, then issue a completion certificate. Removing a breast without this is a common and serious problem found in home-buyer surveys — it can stall a future sale. We provide the engineering in-house and manage the Building Control sign-off as part of the contract.

Is a party wall agreement needed to remove a chimney breast?

Very often, yes — chimney breasts usually sit on the party wall shared with your neighbour, and cutting into that wall, or fixing gallows brackets to it, brings the work under the Party Wall etc. Act 1996. Notice must be served and an award agreed before work starts. Because the neighbour frequently has their own chimney breast backing onto yours, getting this right matters. We serve the notices and agree the award through our sister surveying company.

How long does chimney breast removal take?

A single-floor removal with making-good is typically 1–2 weeks on site; a full-height removal including the stack 2–3 weeks, plus any roof and scaffold time. Add a short period beforehand for the structural design, the Building Control submission and, where needed, the Party Wall award. We provide a programme before work begins.

What happens to the flue, hearth and any remaining fireplace?

We deal with all of it. Where a fireplace is retained above, the flue is supported and, if no longer used, capped and ventilated to prevent damp. Redundant hearths are removed or made good, and any gas connection is safely capped by a Gas Safe engineer. If you are keeping a working fireplace elsewhere, we ensure its flue and structure are unaffected. The result is a clean wall with no trace of where the breast was.

Can you remove the chimney breast and knock through at the same time?

Yes — and it is efficient to do so, because both are structural and usually affect the same rooms. A common project is removing a chimney breast and the dividing wall together to fully open up a reception room. Each element gets its own engineered support and Building Control sign-off, coordinated under one programme. See our knock-through page for the wall-removal side, and we will price and sequence the two together.
Client References

What Our Clients Say

★★★★★

“I would like to thank Ross and his team for their consistent commitment to quality and their unerring reliability. They delivered our property to specification and on time, proving to be an extremely effective, experienced, and proactive contractor.”

James Ward — Investment Director, Belgravia
★★★★★

“We have worked with Ross and his company many times. They are extremely professional and hardworking individuals who can work under any circumstances. There was no variation to the works.”

Cirus Rehman — Finance Director, Grosvenor Street, Mayfair

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Remove Your Chimney Breast

Book a no-obligation consultation at our Finchley Road design studio or in your home. The first meeting is free, lasts 60–90 minutes, and concludes with an honest indication of feasibility, programme and budget band. No salespeople. No pressure.

Call us020 8054 8756
Email uscontact@hampsteadrenovations.co.uk
Visit our studio250 Finchley Road, London NW3

Free Chimney Breast Removal Consultation

Site visit · feasibility assessment · outline cost estimate · programme indication. No obligation. Saturday appointments available.

Enquire before 2pm — same-day call-back (Mon–Fri).

Sister CompanyHampstead Chartered Surveyors & Building Consultancy RICS-regulated surveying — independent advice250 Finchley Road, NW3