Covering Guildford
Alongside Guildford, we also cover Godalming (4 miles to the south-west), Woking and Aldershot.
Homes in the South East
Housing across the South East mixes inter-war semis, post-war estates and older cottages in villages and market towns, so rear and side extensions, hip-to-gable lofts and garage conversions all come up regularly.
What does a double-storey extension involve?
A double-storey extension adds new rooms on both the ground and first floor in one build, typically a larger kitchen or living space downstairs and an extra bedroom or bathroom above. Because the roof and foundations are shared, the cost per square metre is usually lower than a single-storey extension.
- Householder planning application
- Foundations, steelwork, brick and block walls, roof
- Joining the new first floor to the existing landing
How much should I budget for a double-storey extension?
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 |
Do you need permission for a double-storey extension in Guildford?
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.
What can change the price or programme?
- The new roof is tied into the old one, so roof tiles and ridge details need to match.
- The first-floor link can mean moving a bathroom or reshaping the landing.
What happens after I enquire?
- Start with a conversation. A short call or the online form is enough for us to understand what you want to build.
- Survey at your house. We look at the existing structure, services and access, and agree what the design needs to achieve.
- Price and paperwork. The design is priced line by line, and we submit the planning and building control applications.
- We build it. Work follows an agreed programme, with inspections at each stage and a final sign-off.
Questions about a double-storey extension in Guildford
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.
Does a two-storey extension need planning permission?
Usually yes. In England some two-storey rear extensions are permitted development, but side extensions over one storey always need planning permission.
How do I get a price for double-storey extensions in Guildford?
Use the guide price tool for a ballpark figure, then book a visit for a fixed written price for the agreed specification.
Double-storey extensions near Guildford
- Double-storey extensions in Godalming
- Double-storey extensions in Woking
- Double-storey extensions in Aldershot
- Double-storey extensions in Farnborough
Learn more about double-storey extensions, or see every project we cover in Guildford.

