Bexley has more room than most London boroughs: 1930s semis on generous plots in Bexleyheath, Sidcup and Welling, older cottages and village streets in Old Bexley and Crayford, and riverside terraces towards Erith and Belvedere. That space is why extensions and conversions are so common here.
London Building Contractors
Dependable Builders in Bexley for Homes of Every Size
What We Do
Building Services from Bexley Builders
Every service below is delivered by our own in-house tradespeople, fixed-price and fully insured, so you get dependable builders in Bexley from survey to handover.
Loft Conversions in Bexley
Transform your home with expert loft conversions in London by Alpha London Builders. From design and planning to construction, we deliver quality loft conversions tailored to your needs.
Learn more →House Extensions in Bexley
Rear, side return, wraparound and double storey extensions designed and built to fit seamlessly with your London home.
Learn more →Basement Conversions in Bexley
Cellar conversions, basement lowering and full new excavations, engineered and waterproofed to BS 8102 by our in-house team.
Learn more →Garage Conversions in Bexley
Integral, attached and detached garage conversions into bedrooms, offices and annexes, most without planning permission.
Learn more →Property Refurbishment in Bexley
Cosmetic updates through to full structural refurbishments, managed under one dedicated site manager from start to finish.
Learn more →General Building in Bexley
Repointing, roof repairs, damp treatment, brickwork and small structural alterations, carried out by our own trades.
Learn more →Design & Build in Bexley
One team, one contract, one fixed price for design, planning, structural engineering and construction on your project.
Learn more →New Builds in Bexley
New homes and replacement dwellings built from foundation to final finish, with zero-rated VAT on construction costs.
Learn more →Commercial Building in Bexley
Office, retail and restaurant fit-outs across London, delivered around your trading hours with minimal disruption.
Learn more →Residential Building in Bexley
The full range of residential building work, from a single repair to a new build, delivered by one London contractor.
Learn more →Building Demolition in Bexley
Safe, fully licensed demolition work across London, from internal wall removal to complete house demolition ahead of a new build.
Learn more →Why Choose Us
Why Choose Our Bexley Builders
Space to build, planned properly
Wide Bexley plots make side and rear extensions realistic, and we design them around drainage, boundaries and neighbours before pricing.
Garage conversions done to regs
Integral garages are common across Bexleyheath and Sidcup, and we handle the insulation, ventilation and fire-safety sign-off the conversion needs.
Old Bexley and Crayford care
In the conservation areas we match brick, roof detail and windows to the street and deal with the council's conservation officer where needed.
Written, itemised quotes
You get a fixed price after the survey with the scope written down, so there is nothing to argue about later.
Local Knowledge
Building & Planning Considerations in Bexley
Bexley has 23 conservation areas, including Old Bexley, Red House Lane in Bexleyheath, The Green and Christ Church in Sidcup, Foots Cray and North Cray Village. Several of them have Article 4 directions in force, which remove some permitted development rights, so it is worth checking before you assume a rear extension or roof change needs no application. Outside those areas, most semis and detached houses keep the standard rights for single-storey rear extensions and rear dormers.
As Bexley builders, every quote we provide for a Bexley property starts with a check against Bexley Council's conservation area maps and Article 4 register, so you know exactly which route your project needs before any design work begins.
Local Guide
Building in Bexley: what to know before you start
Wide plots, and what they allow
The 1930s semis around Bexleyheath, Welling and Sidcup typically sit on wide plots with side access. That makes side and rear extensions practical, and it leaves room for the driveway once a garage is converted. Old Bexley and Crayford have older, smaller properties where the character of the street matters more. Towards Erith and Belvedere there are Victorian terraces and mid-century estates, and flood zone checks can come into play near the river.
Matching the project to the house
Most Bexley semis have a side garage, so a garage conversion in Bexley is often the simplest way to add a room. Where you need more, an extension across the back or down the side uses the plot well, and a loft conversion adds a bedroom and bathroom without losing any garden. Older houses in Old Bexley or Crayford usually point towards a full refurbishment.
Check these first
Look up your street on the council's conservation area and Article 4 lists. Check the original planning conditions before converting a garage. If a side extension goes up to the boundary, notices under the Party Wall etc. Act 1996 apply. We do all three as part of the free survey and put the answer in writing.
What we do in Bexley: Loft conversions in Bexley · House extensions in Bexley · Basement conversions in Bexley · Garage conversions in Bexley · Property refurbishment in Bexley
Worth reading first: Do you need planning permission for a loft conversion? · How to choose the right builder
Nearby: Builders in Greenwich · Builders in Bromley
Ready to talk? Book a free site survey and we will tell you in writing which planning route your address needs.
Areas We Cover
Areas We Cover in Bexley
Bexleyheath
Sidcup
Welling
Old Bexley Village
Crayford
Erith
Blendon
Barnehurst
Don't see your street listed? Our builders in Bexley cover the whole borough and the surrounding area — get in touch to check.
Our Work
Recent Bexley Projects
A look at recent work carried out for clients in and around Bexley.
Open-Plan Kitchen Renovation
A dated, closed-off kitchen opened up into a bright, modern open-plan kitchen with new cabinetry, worktops, and appliances.
View Project →
Mansard Roof Loft Conversion
An under-used loft transformed into three light-filled bedrooms and a family bathroom, with a full mansard roof extension built to Building Control standards from start to finish.
View Project →What Clients Say
Reviews from Bexley
“Our extension took exactly as long as they told us it would, which after two quotes from other builders felt like a small miracle. Would use them again without hesitation.
”
Amara Okafor
Rear Extension, Leyton
Common Questions
FAQs About Builders in Bexley
Which parts of Bexley have the strictest planning controls?
The 23 conservation areas, which include Old Bexley, Red House Lane, The Green in Sidcup, Foots Cray and North Cray Village. Several carry Article 4 directions as well. The council publishes the list on its Article 4 page, and we check your address against it before quoting.
Can I build a side extension on a 1930s semi in Sidcup or Welling?
Outside a conservation area, a single-storey side extension can be permitted development if it is no wider than half the width of the original house and meets the height limits. Inside a conservation area, side extensions need planning permission. We measure the plot and confirm the route at survey.
Does a loft conversion in Bexley need planning permission?
Rear dormers and hip-to-gable conversions on houses outside conservation areas are normally permitted development, within the 50 cubic metre limit for semi-detached and detached houses. Roof changes on the front slope are not. Building Regulations approval is needed in every case.
Is flood risk a problem near Erith and Belvedere?
It can be. Parts of the riverside fall into Environment Agency flood zones, which can mean a flood risk assessment for an extension and extra detailing on floor levels. Away from the river most of Bexley is not affected. We check the zone for your address during the survey.
Ready When You Are
Get a Free Quote from Our Bexley Builders
Free site survey, a fixed-price quote within 48 hours, and one team from first fix to final handover.
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