Bromley · BR1 · BR2 · BR3
House Extensions in Bromley
Large south-east borough with detached homes suited to double-storey extensions and lofts. Single and double-storey extensions delivered as a fixed-scope design and build package.
Postcodes covered
Quick answer
Builderr delivers house extensions across Bromley — BR1, BR3, BR6 and BR7. Typical Bromley extension cost £42,000–£105,000 over 11–22 weeks. Single and double-storey rears on 1930s semis with bifolds and roof lanterns dominate. Large gardens allow 6m PD rears under Larger Home Extension; double-storey rears common where planning permits.
Bromley
House Extensions specialists across Bromley.
We deliver house extensions projects across the full Bromley postcode set — BR1, BR2, BR3, BR4, BR5, BR6, BR7. Large south-east borough with detached homes suited to double-storey extensions and lofts.
Every Bromley project includes a free desk-based planning assessment before we quote, so you know upfront whether permitted development, prior approval, or full planning applies to your specific address. Our local project manager for Bromley has detailed knowledge of the planning department's preferences, the conservation area boundaries, and the common construction details for the prevailing housing stock here.
Quotes for Bromley house extensions are fixed-scope after a site survey, valid for 60 days, and never carry provisional sums or open-ended day rates. Every project includes our 10-year structural warranty and 12-month defects period.
Planning in Bromley
Local planning rules for house extensions in Bromley.
Bromley's conservation areas include Chislehurst (Webster Place, Camden Park), Beckenham, Bickley, West Wickham, Hayes, Park Langley, Cudham and Petts Wood. The Green Belt covers large parts of southern Bromley restricting new development. Outside Green Belt and conservation areas, Bromley is planning-friendly with strong PD rights. The council favours traditional brick and tile detailing in suburban areas; modern glazed rear extensions are increasingly approved.
Our planning team handles the full submission for Bromley addresses including drawings, Design and Access Statements where required, and pre-application consultation with the council. We tell you whether your house extension is permitted development, prior approval, or full planning before you sign anything.
Builderr vs other London builders.
The construction industry has a wide distribution of operators. Here's what changes between a directly-employed, fixed-scope outfit and the alternatives.
| Criterion | Builderr | Typical London builder | Cowboy outfit |
|---|---|---|---|
| Labour model | Directly employed team (PAYE) | Mixed subcontract gangs | Day-rate cash labour |
| Pricing | Fixed-scope itemised quote | Estimate + provisional sums | Verbal price + variations |
| Design & engineering | In-house architect + SE | Outsourced, separate billing | Builder draws on the back of an envelope |
| Planning + LDC handled | Yes — included in price | Often charged extra | Builder asks you to apply |
| Party wall surveyors | Instructed by us | Your responsibility | Skipped (illegal) |
| Building control | Plans + site inspections booked by us | Building Notice route | Not registered |
| Project management | Dedicated PM, weekly photo updates | Foreman doubles up | Owner-manager juggles 5 jobs |
| Payment schedule | Stage payments against signed-off milestones | Weekly invoices | Cash up front |
| Insurance | £10M PL + 10yr structural warranty | £2–5M PL only | No documented cover |
| Snags at handover | <3 typical | 20–30 typical | Walk-off mid-job common |
| Variation creep | 0% — fixed scope | +15–25% over original quote | +40%+ regularly |
Save £27,000–£60,750 on a house extension in Bromley.
Industry data (FMB, RICS, Which? Trusted Trader 2024) shows the average London construction project overruns by 18–22% on cost and 25–35% on time. Fixed-scope contracts with a single accountable team eliminate that variance. The savings above assume a typical project at £135,000.
FAQ
House Extensions in Bromley.
How much does a house extension cost in Bromley?
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Most house extensions projects in Bromley cost £50,000–£220,000 depending on size, spec and structural complexity. Inner London postcodes typically sit toward the upper end; outer borough projects trend mid-range. All Builderr Bromley quotes are fixed-price with no provisional sums.
Do I need planning permission for a house extension in Bromley?
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Planning rules vary across Bromley. We check permitted development eligibility, conservation area status and any Article 4 directions affecting your specific postcode before quoting. Many house extensions fall under permitted development, but conservation areas and listed buildings need full planning.
How long does a house extension take in Bromley?
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Typical timeline is 10–20 weeks on site, plus 4–8 weeks for design, structural engineering and approvals. If full planning is required (conservation areas, mansards, larger extensions), add 8–12 weeks for the planning decision before site start.
Do you have house extension references in Bromley?
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Yes — we maintain a live reference list for Bromley and can connect you with two or three completed clients within the borough. We've delivered projects across nearly every Bromley postcode since 2022, so most prospective clients can visit a completed project nearby.
What's included in a Builderr house extension quote in Bromley?
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Every Bromley quote covers structural design, party wall notices and surveyor coordination, planning or prior approval submission where required, building control, full build, snagging and a 10-year structural warranty. Kitchen units, sanitaryware and bespoke finishes are itemised separately so you can flex spec without losing fixed-price certainty on the build.
Other services in Bromley
Get a Bromley house extension quote.
Senior consultant call within one business hour. Free desk-based planning assessment for BR1, BR2, BR3 and surrounding postcodes. Fixed-scope price — no provisional sums.
