Extensions in Thatcham: design, planning and build
More space without moving: we plan and build extensions across Thatcham, with one team for the drawings, the council and the build.
- Postcode districtsRG18, RG19
- Price regionSouth East England (×1.12)
- Planning rulesEngland
- Site visitFree, no obligation
Choosing the right extension in Thatcham
The South East has a broad mix of 1930s semis, post-war estates, newer developments and period cottages, and many houses have enough garden for a generous rear extension.
For many houses here, orangery extensions, single-storey rear extensions or double-storey extensions gives the most useful space for the budget.
Planning rules in Thatcham
In England a single-storey rear extension can usually go up to 3 m beyond the original rear wall of a semi-detached or terraced house, or 4 m on a detached house, without a planning application, provided it is no more than 4 m high, keeps eaves to 3 m within 2 m of a boundary and, with other buildings, covers no more than half the land around the original house. The larger home extension prior approval scheme raises those depths to 6 m and 8 m, with neighbours notified and a 42-day decision.
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.
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.
Applications are decided by the local planning authority (your district, borough or unitary council).
Where we work near Thatcham
Across RG18, RG19, we can visit, measure and advise. Neighbouring towns we cover include Newbury (3 miles), Reading (13 miles), Earley (15 miles), Wokingham (18 miles), Crowthorne (20 miles). Just over the Hampshire border, Basingstoke is about 12 miles away.
What extensions cost in Thatcham
Use these Thatcham guide prices to sense-check a budget; the guide-price tool narrows them to your own size, and the site visit turns them into a written figure.
| Extension type | Example size | Standard spec (inc VAT) |
|---|---|---|
| Single-storey rear extensions | 20 m² | £45,500 – £58,500 |
| Kitchen extensions | 20 m² | £47,000 – £59,500 |
| Double-storey extensions | 32 m² | £64,500 – £84,500 |
| Extensions over a garage | 12 m² | £28,000 – £36,500 |
| Orangery extensions | 16 m² | £50,000 – £63,000 |
| Wraparound extensions | 25 m² | £64,000 – £81,500 |
| Side return extensions | 11 m² | £29,500 – £37,000 |
Choose an extension type
- Kitchen extensions · from £30,000
- Timber frame extensions · from £23,500
- Pitched roof extensions · from £24,500
- Building regulations for extensions · from £1,000
- Orangery extensions · from £33,500
- Bedroom extensions · from £29,000
- Flat roof extensions · from £23,500
- Annexe extensions · from £61,500
- Glass box extensions · from £33,500
- Planning permission for extensions · from £350
- Side return extensions · from £20,000
- Conservatory replacement extensions · from £22,000
- Wraparound extensions · from £40,000
- Utility and boot room extensions · from £15,500
- Side extensions · from £24,500
- Home office extensions · from £17,500
- Bungalow extensions · from £29,000
- Extension plans and drawings · from £1,300
- Single-storey rear extensions · from £23,500
- Porch extensions · from £4,450
- Extensions over a garage · from £26,500
- Double-storey extensions · from £42,500
Free site visit
We visit your Thatcham home, measure up, talk through what you want and check the planning position.
Design and approvals
We produce the drawings and structural design, and manage the approvals so they are in place before work starts.
Fixed written price
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Questions about extensions in Thatcham
How much does an extension cost in Thatcham?
Using our South East England factor (×1.12), a standard-spec single-storey extension of 20 m² is a guide £45,500 to £58,500 including VAT, and a 32 m² two-storey extension £64,500 to £84,500. Your written price follows the survey.
Will my neighbours need to be told?
If you apply for planning or prior approval the council notifies them, and in England party wall notices may be needed for work near a shared boundary.
Can I get a price before anyone visits?
Yes. This page shows guide prices adjusted for Thatcham, and the guide-price tool gives a range for your own size and finish in about a minute.
Do you handle building regulations?
Yes. We prepare the drawings and calculations, submit them and book inspections, ending with a completion certificate.
How long does an extension take in Thatcham?
Usually 2 to 4 months of design and approvals, then 10 to 16 weeks on site for a single-storey extension or 16 to 24 weeks for two storeys.
Book a free site visit in Thatcham
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.