Side return extensions in Thatcham: design, approvals and build
Thatcham homeowners can use us for the whole side return extension project: survey, design, planning or permitted development checks, building regulations and the build itself.
- Guide price in ThatchamFrom £20,000 inc VAT
- PlanningOften permitted development; party wall notice usual
- Build time10–14 weeks on site
- Postcode districtsRG18, RG19
Covering Thatcham
We cover Thatcham and the postcode districts RG18, RG19. Nearby, we also take on projects in Newbury (3 miles), Reading (13 miles), Earley (15 miles), Wokingham (18 miles).
For homes towards Hampshire, Basingstoke is around 12 miles away. 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.
Is a side return extension right for your house?
- Victorian and Edwardian terraces with a rear outrigger
- Narrow galley kitchens
- Homes where the garden is too small to lose much depth
Light is the design problem. A side return can make the middle of the house darker if the roof is solid, so we model the daylight and usually recommend a glazed slope or a run of rooflights along the boundary edge.
How much does a side return extension cost in Thatcham?
Labour and material costs vary across the UK, so for Thatcham we use our South East England factor (×1.12). The ranges include VAT and exclude design, structural and council fees.
Typical rates in Thatcham: £2,350 to £4,260 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 1.8 m × 4.5 m 8 m² | £20,000 – £24,000 | £21,500 – £27,000 | £26,500 – £34,500 |
| 2 m × 5.5 m 11 m² | £25,500 – £31,000 | £29,500 – £37,000 | £36,500 – £47,000 |
| 2.2 m × 7 m 15 m² | £35,000 – £42,500 | £40,000 – £50,500 | £50,000 – £64,000 |
For a figure based on your own dimensions, use our guide-price tool.
Do I need planning permission in Thatcham?
In England a single-storey side return infill is often permitted development if it stays within the height limits and is no wider than half the width of the original house. Conservation areas, listed buildings and flats always need an application, and the boundary wall usually brings in the Party Wall Act.
Homes in conservation areas, national parks, National Landscapes (formerly AONBs), the Broads and World Heritage Sites have tighter rules, so we always check the property's status and planning history before design starts.
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).
Our process, step by step
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
We visit your Thatcham home, measure up, talk through what you want and check the planning position.
Design and approvals
We draw the design, agree it with you and handle planning or permitted development checks and building regulations.
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
Our team builds the extension, keeps you updated weekly and finishes with building control sign-off.
Common questions in Thatcham
Will my neighbours in Thatcham be involved?
If a planning application or prior approval is needed, the council notifies neighbours. If the work is on or near a shared boundary, party wall notices may also be needed.
Do you cover all of Thatcham?
Yes. We cover Thatcham and the surrounding parts of Berkshire. Site visits are free and there is no obligation.
How long does a side return extension take to build in Thatcham?
On site, typically 10 to 14 weeks once approvals are in place. Before that, allow 6–12 weeks design and approvals.
Will the kitchen be darker?
Not if the roof is designed well. A glazed roof or a line of rooflights along the boundary usually makes the room brighter than before.
Do side return extensions need planning permission?
In England many single-storey side returns fit within permitted development if they stay within the height limits and are no wider than half the width of the original house. Conservation areas, listed buildings and flats need an application. Other UK nations have their own rules, which we check.
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.