Side extensions for homes in Greater London
If you live in Greater London and want more space without moving, a side extension is one of the most practical ways to get it. We handle the drawings, approvals and the build.
- Guide priceFrom £28,500 inc VAT
- PlanningSingle storey can be permitted development
- Towns covered105
- Site visitFree, no obligation

Towns in Greater London
- Abbey Wood
- Acton
- Barking
- Barnes
- Barnet
- Battersea
- Beckenham
- Becontree
- Bethnal Green
- Bexley
- Blackheath
- Bow
- Brixton
- Brockley
- Camden Town
- Canning Town
- Carshalton
- Catford
- Chalk Farm
- Chelsea
- Chessington
- Chingford
- Chislehurst
- Chiswick
- Coulsdon
- Cricklewood
- Croydon
- Dagenham
- Earlsfield
- East Barnet
- Edmonton
- Eltham
- Enfield
- Enfield Lock
- Feltham
- Finchley
- Friern Barnet
- Fulham
- Golders Green
- Greenford
- Greenwich
- Hampton
- Hanworth
- Harlesden
- Harringay
- Harrow
- Hayes (Hillingdon)
- Heston
- Highbury
- Holloway
- Hook
- Hornchurch
- Hounslow
- Ilford
- Isleworth
- Kilburn
- Leytonstone
- Manor Park
- Mitcham
- Morden
- Muswell Hill
- New Cross
- New Malden
- Norbury
- Northolt
- Notting Hill
- Orpington
- Palmers Green
- Peckham
- Pinner
- Plumstead
- Ponders End
- Purley
- Putney
- Richmond
- Roehampton
- Romford
- Ruislip
- Shepherds Bush
- South Croydon
- South Norwood
- South Ruislip
- Southall
- Stamford Hill
- Stepney
- Stratford
- Streatham
- Surbiton
- Sutton
- Thamesmead
- Tooting
- Tottenham
- Upper Norwood
- Uxbridge
- Wallington
- Walthamstow
- Wealdstone
- Welling
- Wembley
- West Ham
- Willesden
- Wimbledon
- Wood Green
- Woodford Green
- Worcester Park
Side extension prices in Greater London
Prices below are for Greater London, using the London factor of ×1.3. They are guide ranges including VAT for the build only, not a quote.
Typical rates in Greater London: £2,280 to £4,420 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 2.5 m × 5 m 12 m² | £28,500 – £34,500 | £31,500 – £41,500 | £40,500 – £53,500 |
| 3 m × 6 m 18 m² | £40,500 – £49,500 | £47,500 – £62,500 | £60,500 – £80,000 |
| 3 m × 8 m 24 m² | £54,500 – £66,000 | £63,500 – £83,000 | £81,000 – £106,500 |
For a figure based on your own dimensions, use our guide-price tool.
Will the council need to approve it?
In England a single-storey side extension can be permitted development if it is no more than 4 m high and no wider than half the width of the original house. Two-storey side extensions, and any side extension on designated land such as a conservation area, need a householder planning application.
In a conservation area, national park, National Landscape, the Broads or a World Heritage Site the permitted development limits are tighter (no side or two-storey extensions without an application). Listed homes need listed building consent, and if permitted development rights have been removed, any extension needs an application.
Building over or within 3 m of a public sewer needs the water company's consent, usually through a build-over agreement, before the foundations go in.
If the work involves a shared wall, building on the boundary, or digging foundations within 3 m (sometimes 6 m) of a neighbour's building, the Party Wall etc. Act 1996 applies and notice must be served before work starts: two months for work to a party wall, one month for new walls on the boundary and for excavations.
Applications are decided by the local planning authority (your district, borough or unitary council).
Who a side extension suits
- Houses where the rear garden is small
- Detached and semi-detached houses with side land
- Homes needing a utility, study or ground-floor bedroom
Covering Greater London
Towns we cover in Greater London include Bexley, Barking, Sutton, Croydon, Ilford, Enfield, Harrow, Tottenham. In London, space is at a premium and gardens are often short, so side returns, wraparounds and carefully planned rear extensions tend to make the most of every metre.
How the project works
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
First, a site visit: we look at the house, garden, access and drains and listen to what you need.
Design and approvals
We draw the design, agree it with you and handle planning or permitted development checks and building regulations.
Fixed written price
You receive a written, itemised price and programme. Nothing starts until you are happy with it.
Build and sign-off
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Common questions in Greater London
Do I need building regulations approval in Greater London?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Greater London, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
How long does a side extension take to build in Greater London?
On site, typically 10 to 18 weeks once approvals are in place. Before that, allow 6–14 weeks design and approvals.
Can I build over my driveway?
Yes, if the foundations work and you keep any parking the council requires. Drains and services under drives are common, so we check before design.
Can I build a side extension without planning permission?
In England a single-storey side extension can be permitted development if it is no more than 4 m high and no wider than half the width of the original house. Two-storey side extensions, and any side extension on designated land such as a conservation area, need a planning application.
Book a free site visit in Greater London
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.