Thatcham, Berkshire
Semi-detached rear extension in Thatcham
For homes in Thatcham, a semi-detached rear extension is often the simplest way to gain space without moving. Single or two-storey extensions for semi-detached houses, with side access and one party wall. We take it from survey to completion certificate.
We cover Thatcham (RG19) as part of our Berkshire work. Where a Thatcham semi already has a small lean-to at the back, we usually replace it rather than extend it.
Book a free site visit
Tell us about the house and we'll call to arrange a free, no-obligation visit.
How much does a semi-detached rear extension cost in Thatcham?
For Thatcham we work from the South East England rate: £2,130–£3,470 per square metre of new floor, including VAT, standard specification. South East prices run above our West Midlands baseline, mainly on labour rates and clay-soil foundations.
| Size | Guide price inc VAT |
|---|---|
| 3 m wide × 4 m deep (12 m²) | £25,500–£41,500 |
| 4 m wide × 5 m deep (20 m²) | £42,500–£69,500 |
| 4 m wide × 6 m deep (24 m²) | £51,000–£83,500 |
These are guide ranges; the written quote after the survey is the figure that counts.
Do you need planning permission for a semi-detached rear extension in Thatcham?
Whether your semi-detached rear extension in Thatcham needs a planning application depends on its size, your house and any local restrictions.
Under England's householder permitted development rules you can usually add 3 metres at the back of an attached house, or 4 metres on a detached house, without a planning application, as long as the extension stays under 4 metres high and its eaves stay under 3 metres where it is within 2 metres of a boundary.
England's rules allow a rear extension of more than one storey without an application only when it is no deeper than 3 metres and at least 7 metres from the boundary opposite the rear wall, and never on designated land. Most two-storey schemes need householder planning permission.
England also has the larger home extension route: a single-storey rear extension of up to 6 metres on an attached house or 8 metres on a detached house, after prior approval from the council. The council notifies your neighbours and has 42 days to decide; the fee is £249 (£310 for applications made from 8 December 2026). The route is not available on designated land such as conservation areas.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent. Before any drawing we look up the property's history with the council, because earlier extensions and removed rights change the answer.
What are homes in Thatcham like to extend?
Thatcham has a mix of Victorian terraces near the centre and larger Edwardian and inter-war houses further out. Clay soils across much of the South East mean deeper foundations near trees, which we plan for at the survey.
How a semi-detached rear extension in Thatcham comes together
Free site visit
We measure the house and garden, look at the back wall, drainage and boundaries, and talk through what you want from the space.
Options and costs
We draw layout options and price each one, so the budget shapes the design rather than surprising you later.
Planning and regulations
We take the design through the right planning route, then produce the construction drawings and engineer's calculations for building control.
Build and sign-off
We build to the approved drawings with regular updates, then hand over the building control completion certificate and any guarantees from suppliers.
Semi-detached rear extensions near Thatcham
From Thatcham, the nearest places we also cover are Newbury (2.8 miles) and Tadley (6.8 miles).
- Semi-detached rear extension in Newbury
- Semi-detached rear extension in Tadley
- Semi-detached rear extension in Basingstoke
- Semi-detached rear extension in Reading
- Semi-detached rear extension in Didcot
Other work in Thatcham:
FAQ
Semi-detached rear extension questions in Thatcham
Can I live at home while the extension is built?
Usually yes. Most of the work is outside until the back wall is opened near the end, and that stage is screened off.
Do you handle building control in Thatcham?
Yes. We apply to the council or a registered building control approver and hand over the completion certificate.
How long does a semi extension take?
10 to 16 weeks on site for a single-storey extension.
How much does a semi-detached rear extension cost in Thatcham?
As a guide, £2,130–£3,470 per square metre including VAT for a standard specification. For example, 3 m wide × 4 m deep (12 m²): about £25,500–£41,500 at that rate. Your written price follows the survey.
Can you match the brick or stone on my Thatcham house?
We source the closest match and show you samples before ordering; reclaimed materials are often the best match on older houses.
What postcode areas do you cover around Thatcham?
Including RG19, and the surrounding Berkshire area.