Staines-upon-Thames bedroom extensions, designed and built
Thinking about a bedroom extension for your Staines-upon-Thames home? Start with a free site visit: we measure up, check what the council will allow and give you honest guide figures on the day.
- Guide price in Staines-upon-ThamesFrom £29,000 inc VAT
- PlanningUsually a householder application
- Build time14–22 weeks on site
- Postcode districtsTW15, TW18, TW19, TW20
Planning rules that apply in Staines-upon-Thames
In England a two-storey rear extension is permitted development only if it projects no more than 3 m from the original rear wall, sits at least 7 m from the rear boundary, matches the roof pitch and uses obscure, non-opening side windows upstairs. Most two-storey extensions therefore go through a householder planning application, which costs £548 from 1 April 2026 and normally takes about 8 weeks.
Before any drawing is finalised we check whether the house is listed, in a conservation area or subject to an Article 4 direction.
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).
Is a bedroom extension right for your house?
- Homeowners who want an en-suite master bedroom
- Growing families
- Multi-generational households
New bedrooms on an upper floor need an escape window or a protected route to the outside under the building regulations. We design the window sizes and stair route to meet that from the outset.
Extensions in and around Staines-upon-Thames
Our survey diary covers Staines-upon-Thames, including TW15, TW18, TW19, TW20. Nearby, we also take on projects in Egham (2 miles), Ashford, Surrey (2 miles), Sunbury-on-Thames (4 miles), Weybridge (5 miles).
Homes across the South East range from Victorian terraces in the older town centres to large detached houses on the edges, so the right extension type varies street by street.
Bedroom extension prices in Staines-upon-Thames
Labour and material costs vary across the UK, so for Staines-upon-Thames we use our South East England factor (×1.12). The ranges include VAT and exclude design, structural and council fees.
Typical rates in Staines-upon-Thames: £1,790 to £3,580 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| One bedroom 12 m² | £29,000 – £35,500 | £29,000 – £38,000 | £32,000 – £43,500 |
| Bedroom and en-suite 18 m² | £32,000 – £39,500 | £38,000 – £49,500 | £48,000 – £65,000 |
| Two rooms 30 m² | £53,500 – £66,000 | £63,500 – £82,500 | £80,500 – £108,000 |
For a figure based on your own dimensions, use our guide-price tool.
What happens next
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
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
We confirm the build price in writing, based on the approved drawings and the finishes you have chosen.
Build and sign-off
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Common questions in Staines-upon-Thames
Who do I contract with for a bedroom extension in Staines-upon-Thames?
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.
Do you cover all of Staines-upon-Thames?
Yes. We cover Staines-upon-Thames and the surrounding parts of Surrey. Site visits are free and there is no obligation.
Do I need building regulations approval in Staines-upon-Thames?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Does an en-suite need a window?
No, but it needs mechanical extraction that meets the building regulations. We design the duct route at the drawing stage.
How much does a bedroom extension cost?
Our guide range is about £1,790 to £3,580 per m² including VAT. A bedroom with an en-suite of about 18 m² is typically £38,000 to £49,500 at standard spec, depending on whether it is part of a larger two-storey build.
Book a free site visit in Staines-upon-Thames
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.