House extensions in Bexleyheath
Extension builders a few minutes from Bexleyheath, working on the 1930s semis of Barnehurst and Danson Park, the Victorian terraces behind the Broadway and the Red House Lane conservation area.
A ten-minute drive from our base
Kelmend Construction is based in Sidcup, ten minutes from Bexleyheath. The housing here is mostly interwar: long streets of 1930s semis in Barnehurst, around Danson Park and toward Crook Log, with pockets of older Victorian and Edwardian houses around Upton, Red House Lane and behind the Broadway.
Our house extensions service covers all of DA6 and DA7. The 1930s semi is what we build on most, and knowing where Bexley's conservation area and Article 4 rules apply, principally Red House Lane, means fewer surprises.
We know your property
1930s semis
The bulk of Bexleyheath's housing: interwar semis with bay windows, hipped roofs and side passages, laid out in long consistent streets. Almost every one benefits from a rear extension to open up a small original kitchen.
Victorian and Edwardian houses
The older houses around Upton and Red House Lane, close to William Morris's Red House, sit in and around the Red House Lane conservation area, which also carries an Article 4 direction. Extensions here are possible but need planning permission and sympathetic design.
Victorian terraces
The terraces behind the Broadway typically have narrow side returns and modest gardens, well suited to side return and rear extensions that transform a cramped kitchen.
Larger semis and detached
The streets around Danson Park contain larger semis and detached homes on wider plots, suited to double storey rear extensions, side extensions and wraparounds.
Interwar and post-war
Mixed interwar and post-war housing with few planning constraints and straightforward permitted development scope.
1930s estates
Consistent 1930s estates with generous gardens. Planning is generally straightforward and these are often the best-value extension projects in the area.
Types of extension we build in Bexleyheath
Rear extension
The most common extension on the area's 1930s semis, extending the ground floor into the garden for an open-plan kitchen and living space. Outside Red House Lane, most single storey rear extensions are permitted development.
Double storey extension
A larger kitchen below and a bedroom or bathroom above. Suits the wider plots around Danson Park. Always requires planning permission.
Side return extension
Fills in the side passage of the terraces behind the Broadway, turning a narrow kitchen into a wide, light one. Often combined with a rear extension.
Wraparound extension
Rear and side return in one L-shaped build. Popular on Bexleyheath's semis where the side passage allows.
Side extension
Builds into the side passage for a utility room, downstairs WC or home office. Very common across Barnehurst and usually permitted development.
Garden room extension
Large glazed doors, full insulation and integrated heating, built to the same standard as the house. Suits the long gardens of the 1930s streets.
What you need to know before extending in Bexleyheath
Bexleyheath sits in the London Borough of Bexley. Most of the area is outside conservation areas, which makes planning simpler than in neighbouring Sidcup, with Red House Lane the main exception.
Permitted development
Outside conservation areas, most of the borough's 1930s semis qualify for single storey rear extensions under permitted development, with the larger home extension route available for deeper builds subject to neighbour consultation. We confirm the position for your address before any design work.
Conservation areas
Bexley has 23 conservation areas, eight of them in Sidcup alone, plus Old Bexley, Parkhurst and Red House Lane. Within these, extensions visible from the street need planning permission and the council reviews materials and proportions closely.
Article 4 directions
Old Bexley, Old Forge Way, Red House Lane and Brook Street carry Article 4(2) directions that remove some permitted development rights. Work that would be permitted elsewhere needs a full application in these areas.
Suburban character
Bexley's planning policy protects the consistent interwar character of its residential streets. Extensions that respect the roof line, materials and spacing of neighbouring houses are far more likely to be approved.
Approval timelines
Bexley Council typically decides householder applications within 8 weeks of validation. Conservation area applications can take longer. We build realistic timelines into your programme.
Party walls and neighbours
Almost every extension on a semi-detached or terraced property involves the Party Wall Act. We flag this at the consultation so notices can be served early.
Conservation areas near Bexleyheath
Bexleyheath itself has one conservation area, with several more close by in Bexley village and Crayford:
Red House Lane also carries an Article 4 direction. We check your address at the consultation.
Why Bexleyheath homeowners choose us
Based in Sidcup
We're based in Sidcup, so your site visit, your build and any snag afterwards are a few minutes away, not a trip across London.
1930s semi experience
The interwar semi is the borough's dominant house type and it has its own quirks: suspended timber floors, cavity walls of varying quality, side passages of varying widths. We know what to look for before we start.
Bexley Council experience
We know how Bexley's planning department approaches householder applications, which conservation areas bite and which don't, and how to present an application for approval first time.
Directly accountable
You deal with us throughout, not a project manager you've never met. We're on site, we're reachable, and our reputation depends on every local job.
Itemised, honest quotes
Fully itemised quotes with no vague allowances. Any changes are costed in writing before we proceed.
Planning handled
We advise on the planning route, work with architects who know Bexley, and manage building control. You won't be chasing the council yourself.
Our extension process in Bexleyheath
Free consultation and site visit
We come to your Bexleyheath property, walk the space and give you an honest read on what's feasible, which planning route applies for your address and a realistic budget.
Design and planning
We work with your architect, or recommend one who knows Bexley Council, to develop drawings. We advise on the route, submit any application and manage party wall notices.
Detailed quote and contract
Once drawings are finalised we produce a fully itemised quote. Scope, timeline, stage payments and how variations are handled are set out in writing before any work begins.
The build
Work starts on the agreed date. We manage groundworks, structure, trades and materials, with regular photo updates and direct access to us throughout. The site is secured and cleaned every day.
Finishing and fit-out
Plastering, flooring, electrics, plumbing and decoration run as one programme with no gaps between trades.
Handover and sign-off
Bexley building control sign-off is obtained and we walk the finished extension with you to pick up any snags. We don't close the job until you're satisfied.
Covering Bexleyheath and the borough
Based in Sidcup and building across the London Borough of Bexley, including:
Bexleyheath extension FAQs
How much does an extension cost in Bexleyheath?
A single storey rear extension 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. We'll give you an accurate figure after visiting your property.
Do I need planning permission for an extension in Bexleyheath?
Not always. Many single storey rear extensions on 1930s semis fall under permitted development. If your property is in one of the local conservation areas or an Article 4 area, planning permission will be required. We check your specific address at the consultation.
How long does Bexley Council take to approve a planning application?
Bexley Council typically decides householder applications within 8 weeks of validation. Conservation area applications and those with neighbour objections can take longer. We build realistic timelines into your programme.
Will an extension add value to my Bexleyheath home?
In most cases, yes. A well-built extension that turns a small 1930s kitchen into an open-plan family space typically adds 10 to 20% to value, and the local market has rewarded that kind of modernisation consistently. Build quality matters: a poor extension causes problems at sale.
Can I stay in my home during the extension?
In most cases, yes, and most clients do. We plan the work to minimise disruption, particularly during the breakthrough from the existing house, seal off dust, protect flooring and leave the site clean and secure at the end of each day.
How long does a typical extension take to build?
A single storey rear extension takes 10 to 16 weeks from start on site to practical completion. Double storey, wraparound and side extensions take 16 to 24 weeks. Planning permission, where required, adds 8 to 13 weeks before work begins.
Extending your home in Bexleyheath?
We're ten minutes away. Tell us about your project and we'll come round for a free, no-obligation consultation.
No pushy sales. No call centres. Just a straight conversation about your Bexleyheath project.