Side extensions for homes in Wallington
If you live in Wallington 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 price in WallingtonFrom £28,500 inc VAT
- PlanningSingle storey can be permitted development
- Build time10–18 weeks on site
- Postcode districtsSM1, SM2, SM5, SM6
Extensions in and around Wallington
We cover Wallington and the postcode districts SM1, SM2, SM5, SM6. Nearby, we also take on projects in Carshalton (1 mile), Sutton (2 miles), South Croydon (3 miles), Purley (3 miles).
Banstead, in Surrey, is roughly 4 miles from Wallington and also on our list. Across London, terraced houses with narrow side returns and tight access are the norm, which shapes everything from party wall notices to how materials reach the back garden.
Planning and approvals in Wallington
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 regulations approval is separate from planning. In England you can use the council's building control team or a registered building control approver; a full plans application gets the drawings checked before work starts, and the inspector signs the work off with a completion certificate.
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).
What should I budget for a side extension in Wallington?
Labour and material costs vary across the UK, so for Wallington we use our London factor (×1.3). The ranges include VAT and exclude design, structural and council fees.
Typical rates in Wallington: £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 |
Want a range for your exact size? The guide-price tool takes about a minute.
When a side extension makes sense
- Houses where the rear garden is small
- Detached and semi-detached houses with side land
- Homes needing a utility, study or ground-floor bedroom
From first visit to completion
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
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
Design and approvals
Once the layout is agreed, we deal with the council: planning permission or written confirmation that none is needed, plus building control.
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.
Questions people ask about side extensions
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Wallington, 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 Wallington?
On site, typically 10 to 18 weeks once approvals are in place. Before that, allow 6–14 weeks design and approvals.
Do I need building regulations approval in Wallington?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
How much does a side extension cost?
Our guide range is about £2,280 to £4,420 per m² including VAT, depending on specification, so a standard 18 m² single-storey side extension lands around £47,500 to £62,500 in Wallington.
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 Wallington
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.