Side extensions in Southall
Southall homeowners can use us for the whole side extension project: survey, design, planning or permitted development checks, building regulations and the build itself.
- Guide price in SouthallFrom £28,500 inc VAT
- PlanningSingle storey can be permitted development
- Build time10–18 weeks on site
- Postcode districtsTW5, UB1, UB2, UB3, UB4
Included in a typical project
- Structure, roof tied into the house
- Windows, doors and finishes to match
- Foundations near boundaries and any drains
- Survey, design and street-view drawings
Councils often prefer side extensions to sit slightly back from the front of the house with a lower roof, so the original building still reads clearly. We design to those principles from the start to avoid redesigns.
Local to Southall
Site visits are available across Southall (TW5, UB1, UB2, UB3, UB4, W7). We also work in nearby Greenford (2 miles), Heston (2 miles), Hayes (Hillingdon) (2 miles), Isleworth (3 miles).
For homes towards Surrey, Ashford, Surrey is around 7 miles away. 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.
Planning rules that apply in Southall
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.
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.
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.
Applications are decided by the local planning authority (your district, borough or unitary council).
How much does a side extension cost in Southall?
For Southall we adjust our national guide rates by ×1.3, the factor we use for London. Figures include VAT; your written quote after the survey replaces them.
Typical rates in Southall: £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.
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
It starts with a visit to your house to measure, check access and talk through ideas and budget.
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
The build is managed from start to finish, inspected at each stage and signed off on completion.
Side extension questions answered
Who do I contract with for a side extension in Southall?
Your contract is with S&K Property Investments and Improvement Ltd, which designs and manages the project and the build teams who carry it out.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Southall, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Do I need building regulations approval in Southall?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
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.
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.
Book a free site visit in Southall
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.