Covering Berkhamsted
Berkhamsted is about 10 miles west of St Albans. We also cover Hemel Hempstead (5 miles to the east), Amersham and Dunstable.
Homes in the East of England
Across the East of England, newer estates often have integral garages and room for rear extensions, while older towns have Victorian terraces and conservation areas that shape what can be built.
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.
- Measured survey, design and planning drawings
- Householder planning application
- Joining the new first floor to the existing landing
How much does a double-storey extension cost in Berkhamsted?
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 |
What approvals does a double-storey extension need in England?
Projects in England go through two separate checks. Planning (or confirmation that the work is permitted development) comes from the district, borough or unitary council, and building regulations approval comes from the council’s building control team or a registered building control approver. Where work touches a shared wall or digs near a neighbour’s foundations, the Party Wall etc. Act 1996 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 should Berkhamsted homeowners check first?
- 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.
From first call to completion
- Send us the details. Give us a postcode, a rough idea of size and some photos, by phone, form or the guide price tool.
- Free site visit. We measure up, look at access, drains and the structure, and talk through options and budget.
- Drawings, approvals, written quote. We prepare the design, apply for the approvals it needs, and give you a fixed price in writing.
- Build and hand over. Our teams build to the programme, building control inspects, and you get the completion paperwork at the end.
Questions about a double-storey extension in Berkhamsted
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.
How long does a two-storey extension take?
Around 14 to 24 weeks on site, plus the planning period before that.
Can you visit a house in Berkhamsted 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.
Also covering
- Double-storey extensions in Hemel Hempstead
- Double-storey extensions in Amersham
- Double-storey extensions in Dunstable
- Double-storey extensions in Rickmansworth
Learn more about double-storey extensions, or see every project we cover in Berkhamsted.

