Covering Chelmsford
We work in Chelmsford (CM1, CM99) and the places around it, including Billericay, Witham and Maldon.
Homes in the East of England
The East of England has a large stock of post-war and modern estate housing alongside period homes in market towns, which makes garage conversions, single-storey extensions and loft conversions popular.
What goes into a double-storey extension?
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
- Structural engineer’s design and calculations
- Joining the new first floor to the existing landing
What is the guide price for a double-storey extension in Chelmsford?
Typical ranges for double-storey extensions. Ground conditions, access and specification move the final figure, which we fix in writing before work starts.
| 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 Chelmsford?
English projects need planning clearance from the local council, building regulations sign-off from building control, and party wall notices where the work is on or near a shared boundary. We prepare and manage all three.
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 Chelmsford homeowners check first?
- Side extensions close to a boundary are often set back or stepped down so they do not create a terraced effect.
- The new roof is tied into the old one, so roof tiles and ridge details need to match.
What are the steps?
- Tell us about the project. Call, use the guide price tool or send the form with a few photos and a postcode.
- 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.
- We build it. Work follows an agreed programme, with inspections at each stage and a final sign-off.
Double-storey extensions: common questions
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 long does a two-storey extension take?
Around 14 to 24 weeks on site, plus the planning period before that.
Who deals with the council for a project in Chelmsford?
We do. We prepare the drawings, submit planning or permitted development paperwork if needed, and arrange building control inspections.
Also covering
- Double-storey extensions in Billericay
- Double-storey extensions in Witham
- Double-storey extensions in Maldon
- Double-storey extensions in Wickford
Learn more about double-storey extensions, or see every project we cover in Chelmsford.