Side return extensions for homes in Thetford
Thinking about a side return extension for your Thetford 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 ThetfordFrom £19,000 inc VAT
- PlanningOften permitted development; party wall notice usual
- Build time10–14 weeks on site
- Postcode districtsIP24

Do I need planning permission in Thetford?
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.
Before any drawing is finalised we check whether the house is listed, in a conservation area or subject to an Article 4 direction.
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 return extension cost in Thetford?
For Thetford we adjust our national guide rates by ×1.06, the factor we use for East of England. Figures include VAT; your written quote after the survey replaces them.
Typical rates in Thetford: £2,230 to £4,030 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 1.8 m × 4.5 m 8 m² | £19,000 – £23,000 | £20,000 – £25,500 | £25,000 – £32,500 |
| 2 m × 5.5 m 11 m² | £24,000 – £29,500 | £27,500 – £35,000 | £34,500 – £44,500 |
| 2.2 m × 7 m 15 m² | £33,000 – £40,000 | £38,000 – £48,000 | £47,500 – £60,500 |
Try the guide-price tool to see a range for your own size and finish.
Covering Thetford
Our survey diary covers Thetford, including IP24. Neighbouring towns we cover include Wymondham (19 miles), Dereham (20 miles), Norwich (27 miles), King's Lynn (28 miles).
The East of England mixes market-town terraces, inter-war semis and modern estates. Clay soils are common in parts of the region, which can affect foundation design.
Included in a typical project
- Design to keep daylight in the middle of the house
- Party wall notice support (England and Wales)
- New boundary wall or raised party wall
- Survey of the outrigger, boundary wall and drainage
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
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
Design and approvals
We draw the design, agree it with you and handle planning or permitted development checks and building regulations.
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.
Common questions in Thetford
Do I need building regulations approval in Thetford?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Do you cover all of Thetford?
Yes. We cover Thetford and the surrounding parts of Norfolk. Site visits are free and there is no obligation.
Will my neighbours in Thetford 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 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.
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.
Book a free site visit in Thetford
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.