Covering Billericay
Our coverage around Billericay (CM11) also includes Basildon (4 miles to the south) and Wickford.
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 do you get with a double-storey extension?
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.
- Householder planning application
- Structural engineer’s design and calculations
- Foundations, steelwork, brick and block walls, roof
What will a double-storey extension cost?
Indicative costs for double-storey extensions. London and the South East usually sit towards the top of each range.
| 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 |
How is a double-storey extension approved in Billericay?
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?
- 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 happens after I enquire?
- 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.
Questions about a double-storey extension in Billericay
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.
Will we need to move out?
Most people stay. The noisiest stage is when we break through into the existing first floor, which we plan for a short window.
Do you work in Billericay?
Yes. Billericay is within our coverage for double-storey extensions, along with nearby Basildon and Wickford.
Other towns nearby
- Double-storey extensions in Basildon
- Double-storey extensions in Wickford
- Double-storey extensions in Brentwood
- Double-storey extensions in Pitsea
Learn more about double-storey extensions, or see every project we cover in Billericay.

