Extending your home in Runcorn
Planning an extension in Runcorn? Compare extension types, see guide prices adjusted for Runcorn and book a free site visit.
- Postcode districtsWA7, WA8
- Price regionNorth West England (×0.95)
- Planning rulesEngland
- Site visitFree, no obligation
Runcorn extension prices at a glance
We publish guide prices so you can budget before anyone visits. For Runcorn they are adjusted by ×0.95, the factor we use across North West England.
| Extension type | Example size | Standard spec (inc VAT) |
|---|---|---|
| Double-storey extensions | 32 m² | £54,500 – £71,500 |
| Single-storey rear extensions | 20 m² | £38,500 – £49,500 |
| Conservatory replacement extensions | 14 m² | £28,500 – £37,000 |
| Wraparound extensions | 25 m² | £54,500 – £69,000 |
| Kitchen extensions | 20 m² | £39,500 – £50,500 |
| Extensions over a garage | 12 m² | £23,500 – £31,000 |
| Side return extensions | 11 m² | £25,000 – £31,500 |
Planning rules in Runcorn
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 single-storey side extension can be permitted development if it is no more than 4 m high and no wider than half the width of the original house. Two-storey side extensions, and any side extension on designated land such as a conservation area, need a householder planning application.
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.
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.
Applications are decided by the local planning authority (your district, borough or unitary council).
Choosing the right extension in Runcorn
The North West has a high share of Victorian and Edwardian terraces with rear yards and outriggers, plus large areas of inter-war semis in the suburbs.
Start by comparing side return extensions, double-storey extensions and kitchen extensions: between them they cover most of the layouts we see requested for houses like these.
Areas we cover around Runcorn
Across WA7, WA8, we can visit, measure and advise. We also work in nearby Widnes (1 mile), Warrington (7 miles), Ellesmere Port (8 miles), Northwich (10 miles), Chester (12 miles). For homes towards Merseyside, Halewood is around 4 miles away.
All extension types we build in Runcorn
- Side extensions · from £20,500
- Kitchen extensions · from £25,500
- Utility and boot room extensions · from £13,000
- Annexe extensions · from £52,000
- Single-storey rear extensions · from £19,500
- Pitched roof extensions · from £21,000
- Bungalow extensions · from £24,500
- Building regulations for extensions · from £850
- Orangery extensions · from £28,500
- Wraparound extensions · from £34,000
- Flat roof extensions · from £19,500
- Timber frame extensions · from £19,500
- Extension plans and drawings · from £1,100
- Bedroom extensions · from £24,500
- Home office extensions · from £15,000
- Double-storey extensions · from £36,000
- Extensions over a garage · from £22,500
- Glass box extensions · from £28,500
- Planning permission for extensions · from £300
- Porch extensions · from £3,800
- Conservatory replacement extensions · from £19,000
- Side return extensions · from £17,000
Free site visit
We visit your Runcorn 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
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Questions about extensions in Runcorn
How much does an extension cost in Runcorn?
Using our North West England factor (×0.95), a standard-spec single-storey extension of 20 m² is a guide £38,500 to £49,500 including VAT, and a 32 m² two-storey extension £54,500 to £71,500. Your written price follows the survey.
Can I get a price before anyone visits?
Yes. This page shows guide prices adjusted for Runcorn, and the guide-price tool gives a range for your own size and finish in about a minute.
How long does an extension take in Runcorn?
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 Runcorn?
Yes, including the surrounding parts of Cheshire. Site visits are free and there is no obligation.
Do you handle building regulations?
Yes. We prepare the drawings and calculations, submit them and book inspections, ending with a completion certificate.
Book a free site visit in Runcorn
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.