House extensions in Cambridgeshire
Looking to extend your home in Cambridgeshire? Start here: extension types, guide prices for Cambridgeshire, the planning rules that apply and how a project runs.
- Towns listed7
- Price regionEast of England (×1.06)
- Planning rulesEngland
- Postcode districts28
Towns we cover in Cambridgeshire
Towns we cover here include Peterborough, Cambridge, Wisbech, St Neots.
Cambridgeshire extension prices at a glance
Prices on this page use our East of England factor of ×1.06, include VAT at 20% and cover the build; your written price follows a survey and agreed drawings.
| Extension type | Example size | Standard spec (inc VAT) |
|---|---|---|
| Kitchen extensions | 20 m² | £44,500 – £56,500 |
| Wraparound extensions | 25 m² | £60,500 – £77,000 |
| Double-storey extensions | 32 m² | £61,000 – £80,000 |
| Side return extensions | 11 m² | £27,500 – £35,000 |
| Orangery extensions | 16 m² | £47,000 – £59,500 |
| Single-storey rear extensions | 20 m² | £43,000 – £55,500 |
| Conservatory replacement extensions | 14 m² | £31,500 – £41,000 |
Planning rules in Cambridgeshire
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 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.
Which extension suits a Cambridgeshire home?
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.
For many houses here, single-storey rear extensions, bungalow extensions or wraparound extensions gives the most useful space for the budget.
Every extension type in Cambridgeshire
- Side return extensions · from £19,000
- Flat roof extensions · from £22,000
- Double-storey extensions · from £40,000
- Utility and boot room extensions · from £14,500
- Bungalow extensions · from £27,500
- Pitched roof extensions · from £23,500
- Annexe extensions · from £58,000
- Side extensions · from £23,000
- Extensions over a garage · from £25,000
- Wraparound extensions · from £38,000
- Kitchen extensions · from £28,500
- Extension plans and drawings · from £1,250
- Planning permission for extensions · from £350
- Conservatory replacement extensions · from £21,000
- Orangery extensions · from £31,500
- Bedroom extensions · from £27,500
- Home office extensions · from £16,500
- Single-storey rear extensions · from £22,000
- Glass box extensions · from £31,500
- Porch extensions · from £4,200
- Timber frame extensions · from £22,000
- Building regulations for extensions · from £950
Neighbouring areas
Questions about extensions in Cambridgeshire
How much does an extension cost in Cambridgeshire?
With our East of England factor (×1.06), a standard-spec 20 m² single-storey extension is a guide £43,000 to £55,500 including VAT. Prices for every type are linked on this page.
How long does an extension take in Cambridgeshire?
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.
Do you cover all of Cambridgeshire?
Yes, across the whole of Cambridgeshire. Site visits are free and there is no obligation.
Do I need planning permission for an extension in Cambridgeshire?
Not always. It depends on the size, position and your property's history. Many single-storey rear extensions in England are permitted development or can use prior approval.
Book a free site visit in Cambridgeshire
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.