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Do I Need Planning Permission for a Home Extension in Bromley?
A Complete Local Guide for BR1 and BR2 Homeowners

By Buildaway — Home Extension Specialists in Bromley

Published: January 20269 min read
Home Extension in Bromley

Extending Your Home in Bromley: What You Need to Know

Bromley (BR1 and BR2) is one of South-East London’s most popular areas for home extensions, thanks to its large plots, spacious 1930s semis, Victorian terraces, and family-focused neighbourhoods. Whether you’re near Bromley South Station, the green spaces around Martin’s Hill, close to Sundridge Park, or in the quiet residential pockets of Bickley and Widmore, extending your home can significantly increase space, comfort, and property value.

But before you get started, homeowners almost always ask the same essential question: Do I need planning permission for a home extension in Bromley?

This guide explains planning rules, costs, regulations, extension limits, the 2m boundary rule, and what happens if you extend without permission — all tailored to Bromley.

Do You Need Planning Permission for a Home Extension in Bromley?

The good news is many home extensions in Bromley do NOT need planning permission, as they fall under Permitted Development (PD) rights. However, there are limits, rules, and local considerations you need to understand.

Extensions That Usually DO NOT Require Planning Permission (Under PD)

You can generally extend without planning permission in Bromley if:

  • The extension is single-storey
  • It is up to 3m deep for semis/terraces
  • It is up to 4m deep for detached homes
  • Maximum height is 4m at eaves
  • Total height does not exceed the existing house
  • Materials are similar to the existing house
  • No verandas, balconies, or raised platforms are added
  • The extension doesn’t cover more than 50% of the original garden area

This applies to most areas including Bromley Common, Hayes, Sundridge Park, Shortlands, Downham, and Bromley North.

Larger Home Extensions (Still Without Planning Permission)

Under the Householder Prior Approval Scheme, you can extend:

  • Up to 6m on a semi-detached or terraced home
  • Up to 8m on a detached home

…but you must submit a Neighbour Consultation Scheme application (not full planning).

Extensions That DO Require Planning Permission

You WILL typically need planning permission if:

  • You live in a conservation area (parts of Bickley, Bromley Town Centre, Sundridge Park)
  • Your extension is double-storey
  • You want to build forward of the front elevation
  • You’re adding a wrap-around extension
  • You are raising the roof or altering ridge height
  • You want unique external finishes not consistent with the existing building

If you don’t know whether your home falls under restrictions, Buildaway can check it instantly.

The 2m Boundary Rule Explained

The 2m boundary rule restricts the height of walls, eaves, or fencing built within 2m of a boundary line. For extensions under PD:

  • Eaves cannot exceed 3m if they are within 2m of the boundary

This often impacts side extensions and rear wraps common in Bromley’s 1930s housing stock.

What Happens If You Don’t Get Planning Permission?

If your project required planning permission and you didn’t apply:

  • The council can issue an enforcement notice
  • You may be required to undo the work
  • It can delay or block future property sales
  • Mortgage lenders may refuse financing

Always check before building — or ask Buildaway’s team, who handle permissions for Bromley homeowners daily.

How Much Does a Home Extension Cost in Bromley?

Your home extension cost depends on size, structure, glazing, and spec level. Below is a reliable Bromley-specific guide based on typical project ranges.

Extension Type Typical Total Cost
Single-Storey Rear Extension £2,200–£2,800 per m² (build-only) / £2,800–£3,500 per m² turnkey
Double-Storey Extension £2,000–£2,600 per m² (build-only) / £2,600–£3,300 per m² turnkey
Side Return Extension £2,200–£2,900 per m²
Wrap-Around Extension £2,400–£3,400 per m²

Common Additional Costs

  • Kitchens: £10,000–£25,000+
  • Bathrooms: £6,000–£15,000+
  • RSJ/Structural Steel: £2,000–£6,000+
  • Heating upgrades / Megaflo: £2,500–£4,500
  • Glazing & bifolds: £3,000–£8,000+

These figures reflect realistic home extension costs UK for Bromley and surrounding areas.

Home Extension Ideas for Bromley Homes

Popular home extension ideas include:

  • Open-plan kitchen-diner with island
  • Rear extensions for family rooms
  • Double-storey rear additions for bedrooms + en-suite
  • Side returns for extra width in Victorian terraces
  • Utility rooms, pantries, and home offices
  • Large glazing and rooflights for natural light

Homes around Widmore Road, Shortlands, Hayes, and Bromley Common benefit greatly from modern open-plan layouts.

Home Extension Building Regulations in Bromley

Even when planning permission isn’t needed, Building Regulations always apply.

Buildaway ensures compliance with:

  • Part A (structure/RSJs)
  • Part B (fire safety)
  • Part F (ventilation)
  • Part L (thermal efficiency)
  • Part P (electrical)
  • Drainage & foundations

All inspections and certification are handled on your behalf.

FAQs (Updated Sequence)

Q1: Do I need planning permission for an extension in the UK?

Not always. Many single-storey rear extensions fall under Permitted Development.

Q2: How much can I extend my home without planning permission?

Up to 3–4m depth under standard PD, or up to 6–8m under the Larger Home Extension Scheme.

Q3: What happens if I extend without planning permission?

The council can enforce removal, stop works, or affect future sales.

Q4: How much does a two-storey extension cost?

In Bromley, double-storey extensions generally range £80,000–£130,000+ depending on m² and specification.

Q5: What size building can I build without planning permission in the UK?

You can extend up to 50% of your original garden area, subject to height and boundary limits.

Bringing It All Together

Whether you live near Bromley South, the peaceful lanes of Hayes, or the period homes of Sundridge Park, a home extension is one of the most powerful ways to increase space and raise property value.

Buildaway handles everything from design, structural engineering, and planning submissions to full build delivery — ensuring your project stays compliant, on budget, and beautifully finished.

We Serve Bromley and Surrounding Areas

Find us in the heart of Bromley. We are proud to serve our local community.

Nearby Areas We Serve

Below are some of the local areas where you can find Buildaway transforming homes.

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