Covering Crawley
We work in Crawley (RH11, RH77) and the places around it, including Horley, Horsham and East Grinstead.
Homes in the South East
Many South East homes are inter-war or post-war semis and detached houses with room for rear and side extensions, while historic town centres and villages bring conservation area and listed building controls.
What does a double-storey extension involve?
Two-storey work has to sit comfortably with the house and the neighbours, so most of the design effort goes into the roofline, window positions and how the new first floor connects to the landing. We handle the planning application, the structural design and the building control process, then build, roof and finish both floors.
- Measured survey, design and planning drawings
- Foundations, steelwork, brick and block walls, roof
- Windows, insulation, plastering, electrics and plumbing
What will a double-storey extension cost?
Use these ranges to budget for double-storey extensions; the survey turns them into a fixed price for the agreed specification.
| Double-storey extensions | Guide price incl. VAT |
|---|---|
| Standard specification | £2,400 to £2,900 per m² |
| Good specification | £2,900 to £3,400 per m² |
| High specification | £3,400 to £3,850 per m² |
Planning and building rules in Crawley
In England we deal with the council’s planning team for permission or a lawful development certificate, with building control (the council or a registered building control approver) for inspections, and with neighbours under the Party Wall etc. Act 1996 where it applies.
Two-storey rear extensions can sometimes be permitted development in England (no more than 3 m deep, at least 7 m from the rear boundary, roof pitch to match), but most two-storey and all two-storey side extensions need householder planning permission. Expect around eight weeks for a decision once the application is validated.
What can affect a double-storey extension?
- Neighbours’ light is assessed using the 45-degree guide many councils use.
- The first-floor link can mean moving a bathroom or reshaping the landing.
How does the project run?
- Send us the details. Give us a postcode, a rough idea of size and some photos, by phone, form or the guide price tool.
- Survey at your house. We look at the existing structure, services and access, and agree what the design needs to achieve.
- Drawings, approvals, written quote. We prepare the design, apply for the approvals it needs, and give you a fixed price in writing.
- Construction and completion. One site lead co-ordinates every trade through to the building control certificate.
What people ask before starting
How much does a two-storey extension cost?
Typically about £2,400 to £3,850 per square metre of new floor area including VAT. A 40 m² extension across two floors is often around £100,000 to £150,000 depending on specification.
Is a two-storey extension better value than a single-storey one?
Per square metre, usually yes, because the foundations and roof serve two floors of space.
Can you visit a house in Crawley to quote?
Yes. After a short call we arrange a site visit to measure up and agree what the design needs to do, then send a written price.
Other towns nearby
- Double-storey extensions in Horley
- Double-storey extensions in Horsham
- Double-storey extensions in East Grinstead
- Double-storey extensions in Reigate
Learn more about double-storey extensions, or see every project we cover in Crawley.