Chimney Breast Removal in London Homes

Chimney breasts in Victorian and Edwardian London homes often feel like space-wasting relics in modern living. These large brick projections into rooms can make furniture arrangement awkward and reduce usable floor space. Many homeowners consider removing them to reclaim space and create cleaner, more contemporary interiors. However, chimney breast removal is complex structural work requiring careful planning, proper engineering, building control approval, and often party wall agreements. This guide explains everything you need to know about safely and legally removing chimney breasts from London properties.

Understanding Chimney Breasts

Chimney breasts are the internal projections housing chimney flues. In typical Victorian terraces:

• Ground floor chimney breast typically 1-1.2m wide, projecting 300-450mm into room
• First floor breast sits directly above ground floor breast
• Both are supported by foundations at ground level
• Flues run up through breast to chimney stack on roof
• In terraced houses, often shared with neighbours (party wall)
• Constructed from solid brick, very heavy (several tonnes)

This mass of brickwork takes up significant floor space—a typical chimney breast occupies 0.4-0.6 square metres per floor.

Why Remove Chimney Breasts?

Space Reclamation: Removing breasts creates more usable floor area, particularly valuable in smaller London properties.

Improved Layout: Flat walls allow better furniture placement and more flexible room arrangements.

Modern Aesthetic: Clean walls suit contemporary interior design better than protruding breasts.

Practical Benefits:

• Easier to install fitted wardrobes and storage
• Simpler to arrange bedrooms with double beds
• More wall space for kitchen units
• Cleaner lines in living spaces

When to Keep Chimney Breasts

Before deciding on removal, consider:

Character and Value: Original fireplaces and chimney breasts add period character that buyers value. Removing them can actually reduce property values in conservation areas where character is prized.

Working Fireplaces: If you use or might want to use the fireplace, keep the breast. Reinstating after removal is very expensive.

Listed Buildings: Removal usually not permitted without special consent, rarely granted.

Beautiful Original Features: Ornate Victorian or Georgian fireplaces are worth preserving—they're irreplaceable.

Cost vs. Benefit: Removal costs £1,500-£4,000+ per breast. Is the space gained worth this investment?

Structural Considerations

Chimney breast removal is significant structural work:

Load Transfer: The breast above a removed section loses its support. This weight (often 2-4 tonnes) must be transferred to adjacent walls via steel or concrete beams.

Three Removal Scenarios:

1. Ground Floor Only: Most common and simplest:

• Remove ground floor breast, retain first floor breast
• Install steel cantilever or gallows brackets supporting first floor breast
• Beams tied into party walls or external walls
• Structural engineer designs support system
• Cost: £1,500-£2,500 per breast

2. First Floor Only: Less common:

• Remove first floor breast, retain ground floor
• Ground floor breast remains self-supporting
• Must cap and seal flue to prevent draughts
• Simpler than ground floor removal
• Cost: £1,200-£1,800 per breast

3. Complete Removal (Both Floors): Most complex:

• Remove both ground and first floor breasts
• Chimney stack above roof level also removed or supported
• Extensive structural work required
• Roof repairs where stack removed
• Party wall implications significant
• Cost: £3,500-£6,000+ including roof work

Engineering and Support Systems

Cantilever Beams: Most common support method:

• Steel beams built into party walls either side
• Support remaining breast above
• Typically 150-200mm deep RSJs
• Must embed minimum 225mm into supporting walls
• Load calculations by structural engineer

Gallows Brackets: Alternative system:

• Steel brackets fixed to party walls
• Support breast from sides
• Less invasive than full cantilever beams
• Suitable for lighter loads

Concrete Beams: Sometimes used:

• Reinforced concrete instead of steel
• Can be more economical
• Heavier and bulkier than steel

Party Wall Requirements

In terraced and semi-detached properties, chimney breasts often share party walls:

Party Wall Act Compliance Essential:

• Removal affects party walls—requires party wall agreement
• Serve notices minimum 2 months before work
• Appoint party wall surveyor if neighbour doesn't consent
• Schedule of condition documents neighbouring property
• Party wall award specifies work methods and protections
• Cost: £1,200-£2,500 typically for surveyor fees

Neighbour's Breast: If neighbour's chimney breast remains:

• You're removing support from their side
• Must ensure adequate support left for their breast
• Neighbour may require you to support their breast if removing yours creates instability
• Complex situations require expert surveyor advice

Building Control Approval

Chimney breast removal requires building control approval:

• Submit structural engineer's calculations and drawings
• Building control reviews and approves design
• Inspections at key stages during work
• Approval of completed work before plastering
• Completion certificate issued when approved
• Cost: £300-£600 for building control fees

Working without approval is illegal and causes serious problems when selling—buyers' solicitors require proof of approval.

The Removal Process

1. Surveys and Design (2-4 weeks):

• Structural engineer surveys property
• Designs support system
• Produces calculations and drawings

2. Approvals (8-12 weeks):

• Serve party wall notices
• Submit building control application
• Await approvals

3. Preparation (1-2 days):

• Protect floors and belongings
• Install dust barriers
• Set up waste disposal

4. Support Installation (1-2 days):

• Install temporary supports (acrow props)
• Create pockets in walls for beams
• Install steel beams or brackets
• Secure beams properly

5. Breast Removal (1-2 days):

• Carefully dismantle brickwork
• Remove rubble (very heavy—1-2 tonnes typically)
• Cap and seal any exposed flues
• Ensure proper ventilation if flues remain above

6. Making Good (2-3 days):

• Build out wall to match surrounding plaster
• Plasterboard or skim plaster for smooth finish
• Match existing skirting and coving
• Redecorate to match room

Total time: 3-4 months from initial survey to completion (mostly waiting for approvals), 5-7 days of active work.

Costs of Chimney Breast Removal

Ground Floor Breast Removal: £1,500-£2,500

• Includes structural engineering
• Steel beams and installation
• Removal and disposal
• Making good and plastering
• Building control fees

First Floor Breast Removal: £1,200-£1,800

• Simpler as no beam required
• Still needs building control
• Flue capping and sealing

Complete Removal (Both Floors): £3,500-£6,000+

• More complex structural work
• Chimney stack removal or support
• Roof repairs where stack removed
• Scaffolding costs

Additional Costs:

• Party wall surveyor fees: £1,200-£2,500
• Structural engineer: £400-£800
• Building control: £300-£600
• Redecoration after work: £300-£800 per room

Ventilation of Remaining Flues

If removing ground floor breast but keeping upper floors and chimney stack, proper ventilation is critical:

• Sealed unvented flues can accumulate moisture causing damp
• Install air bricks at low level for ventilation
• Ensure chimney pots remain open at top
• Consider cowls to prevent rain entry while allowing ventilation
• Building regulations require adequate flue ventilation

Common Problems and Solutions

Inadequate Support: Most serious issue:

• If beams undersized or poorly installed, breast above can collapse
• Always use qualified structural engineer
• Ensure building control inspects beams before sign-off

Damp from Unvented Flues:

• Cap flues properly at removal point
• Provide ventilation to remaining flues
• Check chimney pots remain clear

Cracking in Neighbouring Properties:

• Proper party wall agreements protect both parties
• Schedule of condition proves when damage occurred
• Work carefully to minimise vibration

Poor Making Good:

• Ensure plaster matches existing
• Skirting and coving should align
• Allow proper drying time before decorating

Alternatives to Complete Removal

If full removal seems too complex or expensive, consider:

Reducing Projection: Cut back breast depth without removing entirely:

• Reduces projection by 100-150mm
• Still provides some extra space
• Much simpler than complete removal
• Less structural work required
• Cost: £600-£1,200

Incorporating into Design: Work with breast rather than against it:

• Build alcove shelving
• Create feature with different paint colours
• Use recess for TV or artwork
• Add storage either side

Restore Rather than Remove: In period properties:

• Restore fireplace as character feature
• Adds value rather than removing it
• Provides attractive focal point
• Can install gas fire or wood burner