House Extensions
in
Bromley
Building bespoke extensions across the London Borough of Bromley — from Victorian terraces in Shortlands to 1930s semis in Bickley and Petts Wood, and detached homes in Chislehurst. Local knowledge, end-to-end management, honest pricing.
Proudly Serving Bromley
Planning to Handover
Free Site Consultations
A Borough Built
to be Extended
Bromley is one of the most rewarding boroughs in London to extend in. With its mix of late Victorian and Edwardian terraces in Bromley town and Shortlands, generous 1930s semi-detached estates in Bickley, Petts Wood, and Park Langley, and substantial detached homes in Chislehurst and Hayes, almost every property type here lends itself to extension — and the local property market typically rewards good quality work with strong returns.
At Kelmend Construction, our house extensions service covers all of South London, and we've worked on projects across the Bromley borough — we understand its specific quirks. The conservation area constraints, the Article 4 directions that restrict permitted development in certain neighbourhoods, the design preferences of Bromley Council's planning department, and the typical configurations of each property type. That knowledge means fewer surprises on your project — and a result that fits the property properly.
We Know
Your Property
Victorian Terraces
Bromley's Victorian terraces — particularly common around Shortlands, Bromley North, and stretches of the town centre — typically have narrow side returns and rear gardens that make them ideal candidates for combined side return and rear extensions. These properties were not built with modern kitchen and living habits in mind, and a wraparound extension can transform the entire ground floor.
Edwardian Semis
The Edwardian semi-detached homes scattered through Beckenham, parts of Bromley Common, and outer Bromley are typically more generously proportioned than their Victorian predecessors but often still benefit hugely from a rear or side return extension to open up the kitchen and create modern open-plan living space. Often well-suited to side extensions where the side passage allows.
1930s Mock Tudor Semis
The 1930s estates of Bickley, Petts Wood, and Park Langley are among the most distinctive in South London — mock Tudor semis with bay windows, generous gardens, and pitched roofs that lend themselves to both ground-floor extensions and double-storey side extensions. Petts Wood and Park Langley are conservation areas, so design quality and material choice matter.
Detached Properties
The detached homes of Chislehurst, Hayes, and parts of Bickley typically sit on generous plots and offer the most options — single or double-storey rear, side, and wraparound extensions all become viable. Many of these properties sit within conservation areas, so design sensitivity is essential, but the rewards in terms of usable space and added value are substantial.
Post-War & 1950s Housing
Pockets of post-war and 1950s housing in parts of Hayes, West Wickham, and the Bromley/Orpington border are usually more straightforward to extend than the conservation area stock — typically with fewer planning constraints and more generous permitted development scope. These properties often deliver the highest return on investment per pound spent.
Modern Housing
Newer housing developments across the borough — including modern estates in and around Bromley town centre — typically come with restrictive estate covenants alongside standard planning rules. We check both before quoting. Extensions to modern properties usually focus on garden rooms, single-storey rear extensions, and side returns where the layout allows.
Types of
Extension
Rear Extension
Extends your ground floor into the rear garden — most commonly used to enlarge the kitchen or create open-plan living and dining space. Single-storey rear extensions often fall under permitted development across Bromley, but check before you assume — properties in conservation areas like Bickley or Chislehurst have tighter restrictions.
Double Storey Extension
Adds rooms on both floors — typically a larger kitchen below and an extra bedroom or bathroom above. Always requires planning permission. In Bromley, the council pays close attention to design quality, materials, and how the extension reads against neighbouring properties, particularly in suburban areas with consistent streetscapes.
Side Return Extension
Fills in the narrow alleyway alongside Victorian and Edwardian terraced houses — particularly common in Shortlands and around Bromley town. Transforms cramped kitchens into wide, open spaces flooded with natural light. Often combined with a rear extension to form a full wraparound.
Wraparound Extension
Combines rear and side return into a single L-shaped build — the most expansive single-storey option for terraced and semi-detached properties. Dramatic results: opens the entire rear and side of the property into one continuous living space. Requires planning permission and careful structural design.
Side Extension
Builds outward into the side garden of a semi-detached or detached property — particularly common on 1930s semis in Bickley and Petts Wood. Can add a garage, utility room, home office, or extend an existing room. In Petts Wood, where the conservation area applies, side extensions need careful design to respect the original streetscape.
Garden Room Extension
A full-build extension designed to blur the line between inside and out — large glazed doors, quality insulation, integrated heating. Particularly popular on Bromley's generously sized plots in Chislehurst, Hayes, and the leafier parts of Bickley. Built to the same structural standard as the rest of your home.
What You Need
to Know
Bromley has a number of planning quirks worth understanding before you start designing your extension. We deal with these every day — here's a summary of what affects most homeowners across the borough.
Article 4 Directions
Bromley has Article 4 Directions in several conservation areas that remove some or all permitted development rights. This means extensions which would be permitted elsewhere require full planning permission in these areas — we check this for your specific property before quoting.
Conservation Areas
Bromley contains around 40 conservation areas — among the most of any London borough. These include Bickley, Chislehurst, Petts Wood, Park Langley, Shortlands, Hayes, and Sundridge. If your property sits within one, design quality, materials, and proportions become critical to gaining approval.
Permitted Development
Outside conservation areas and Article 4 zones, many single-storey rear extensions fall under permitted development — meaning no full planning application is required. We confirm your eligibility against the size, height, and material rules at the start of every project.
Suburban Character
Bromley Council's Local Plan strongly emphasises protecting the borough's suburban character. Extensions which dramatically alter the street-facing appearance, dominate neighbouring properties, or use unsympathetic materials can run into objections — we design accordingly from day one.
Typical Approval Timelines
Bromley Council typically processes household planning applications within 8 weeks of validation, though more complex applications can take longer. We allow for this in your programme so the build start date isn't pushed by last-minute approval delays.
Party Wall & Neighbours
Most extensions in Bromley involve party wall considerations — particularly on terraced and semi-detached properties. We flag this early so notices can be served promptly and any agreements reached before work is due to start.
Working in
Conservation Areas
Bromley has more conservation areas than almost any other London borough. If your property falls within one — and many in the leafier parts of the borough do — design sensitivity and material quality are essential. We have experience working in all of the following areas:
Not sure if your property is in a conservation area? It's worth checking before any design work begins — the constraints are significantly different. We'll confirm for your specific address at the consultation stage and explain what it means for your project.
Why Bromley
Homeowners Choose Us
Local Bromley Knowledge
We've worked across the borough — Bickley, Shortlands, Chislehurst, Petts Wood, Bromley town, Beckenham, Hayes. We know the property types, the planning constraints, and the council's design preferences before we even visit your home.
Conservation Area Experience
Working in conservation areas requires a different approach — material choices, design sympathy, and engagement with the council all matter more. We've done it across Bromley's conservation areas and know how to get extensions approved without compromising on what you want.
Family-Run, Directly Accountable
You deal with us throughout — not a project manager passing the job on. We're on site, we're reachable, and our reputation depends on every Bromley job we do.
Itemised, Honest Quotes
Detailed, line-by-line quotes — no vague allowances, no surprises. Any changes are costed in writing before we proceed. This matters especially on higher-value Bromley properties where the project costs are substantial.
Planning Handled
We don't just build — we advise on planning routes, work with your architect (or recommend one we trust), and manage the building control process. You're not chasing the council or coordinating consultants on your own time.
Quality That Reflects the Property
Bromley's property market rewards quality. A poorly built extension is visible, drags down value, and creates problems at sale. We build to a standard appropriate to the homes we work on — and the standard our reputation depends on.
Our Extension
Process in Bromley
Free Consultation & Site Visit
We come to your Bromley property, walk the space, and discuss what you want to achieve. We give you an honest read on what's feasible, what planning route applies for your address (including conservation area or Article 4 constraints), and the budget you're realistically looking at.
Design & Planning
We work with your architect — or recommend one we trust who knows Bromley's planning department — to develop drawings. Once finalised, we advise on the route: permitted development, householder application, or full planning. We can also manage party wall notices if needed.
Detailed Quote & Contract
Once planning is approved and drawings are finalised, we produce a fully itemised quote. The contract is clear: scope, timeline, stage payments, and how variations are handled.
The Build
Work starts on the agreed date. We manage groundworks, structure, trades, and materials. Regular photo updates and a direct line to us throughout. Site secured and cleaned every day — important on Bromley's typically well-kept streets where neighbours notice.
Finishing & Fit-Out
Plastering, flooring, electrics, plumbing, decoration — all coordinated to flow seamlessly from structural work, keeping the programme on track without gaps between trades.
Handover & Sign-Off
Bromley Council building regulations sign-off obtained. Full snagging walkthrough with you. We don't close the job until you're satisfied — and we're on the end of the phone if anything comes up after completion.
Covering the
Whole Borough
We carry out house extensions across the London Borough of Bromley. Our core areas include:
Bromley Extension
FAQs
How much does an extension cost in Bromley?
A single storey rear extension in Bromley typically costs between £1,500 and £2,200 per square metre, depending on size, specification, and finish. A 20m² kitchen extension might range from £30,000 to £50,000 fully finished. Bromley's higher-end areas — Bickley, Chislehurst, and Park Langley — often involve higher-specification builds with corresponding costs. Double storey extensions cost more in total but less per square metre. We'll give you an accurate figure after visiting your property and discussing what you want to achieve.
Do I need planning permission for an extension in Bromley?
Not always. Many single storey rear extensions in Bromley fall under permitted development — meaning no planning application is required, provided the extension meets size and design criteria. However, if your property is in one of Bromley's many conservation areas, has an Article 4 Direction restricting permitted development, or the extension exceeds permitted development limits, you will need full planning permission. We assess this for your specific property at the consultation stage.
How long does Bromley Council take to approve a planning application?
Bromley Council typically processes household planning applications within 8 weeks of validation. More complex applications — or those that attract neighbour objections — can take longer. Applications for properties in conservation areas often require additional design review and may extend the timeline. We build this realistically into your programme so the build start date isn't pushed back by approval delays.
What is the Article 4 Direction in Bromley?
An Article 4 Direction is a planning rule that removes some or all permitted development rights from a defined area. In Bromley, several conservation areas have Article 4 Directions in place — particularly affecting things like side extensions, roof extensions, and changes to external features that would normally be permitted without planning. If your property is affected, extensions which would be permitted elsewhere require a full planning application. We check this at the start of every project.
Which areas of Bromley are conservation areas?
Bromley has around 40 conservation areas — among the most of any London borough. Major ones include Bickley, Chislehurst (which has multiple distinct conservation areas), Petts Wood, Park Langley, Shortlands, Hayes, Sundridge, and Bromley Common. If your property is in or near any of these, additional design considerations apply. The full list and boundary maps are available on Bromley Council's website, or we can check for your specific address.
Will an extension add value to my Bromley home?
In most cases, significantly. Bromley's property market typically rewards good quality extensions with strong returns — a well-built kitchen extension or additional bedroom can add 10–20% to a property's value, and the absolute returns in Bickley, Chislehurst, Park Langley, and Petts Wood can be substantial given the underlying property prices. The build quality matters enormously, though: a poorly executed extension can cause problems at sale and ultimately cost you more than it added.
Can I stay in my Bromley home during the extension?
In most cases, yes — and most of our Bromley clients do. We plan the work carefully to minimise disruption, particularly when we break through from the existing house into the new extension. We seal off dust, protect flooring and furnishings, and always leave the site clean and secure at the end of the day. For more complex builds — full wraparounds, double storey extensions — there may be short periods where temporary relocation makes sense, which we discuss honestly at the planning stage.
How long does a typical Bromley extension take to build?
A typical single storey rear extension takes 10 to 16 weeks from start on site to practical completion. Double storey, wraparound, and side extensions on larger Bromley properties may take 16 to 24 weeks. This is build time only — planning permission (where required) typically adds 8 to 13 weeks in Bromley before any work can begin. We'll give you a realistic programme in your quote and stick to it.
Extending Your
Home in Bromley?
Tell us about your project and we'll come to you for a free, no-obligation consultation across the borough.
No pushy sales. No call centres. Just a straight conversation about your Bromley project.