Wraparound extensions in Brentwood: design, approvals and build
A wraparound extension in Brentwood starts with the right design and the right approval route. We take care of both, then build it with our own project management.
- Guide price in BrentwoodFrom £38,000 inc VAT
- PlanningUsually a householder application
- Build time14–20 weeks on site
- Postcode districtsCM13, CM14, CM15
Will the council need to approve it?
In England a wraparound extension is assessed as both a side and a rear extension, and the combination usually falls outside permitted development, so most need a householder planning application (£548 from 1 April 2026).
The planning position for a specific Brentwood address depends on its history and any designations, which is why we check it at the first visit.
Building regulations approval is separate from planning. In England you can use the council's building control team or a registered building control approver; a full plans application gets the drawings checked before work starts, and the inspector signs the work off with a completion certificate.
Building over or within 3 m of a public sewer needs the water company's consent, usually through a build-over agreement, before the foundations go in.
Applications are decided by the local planning authority (your district, borough or unitary council).
Is a wraparound extension right for your house?
- Families who want kitchen, dining and living in one space
- Terraced houses that want the largest ground floor possible
- Semi-detached houses with a side passage
The corner is where wraparounds succeed or fail. We usually use a single steel goalpost or a corner post hidden in a pier, and set the glazing so the new room reads as one space rather than two boxes.
Wraparound extension prices in Brentwood
For Brentwood we adjust our national guide rates by ×1.06, the factor we use for East of England. Figures include VAT; your written quote after the survey replaces them.
Typical rates in Brentwood: £2,120 to £3,920 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| Compact L-shape 18 m² | £38,000 – £46,000 | £43,500 – £55,500 | £55,000 – £71,000 |
| Medium L-shape 25 m² | £53,000 – £64,000 | £60,500 – £77,000 | £76,500 – £98,500 |
| Large L-shape 32 m² | £67,500 – £81,500 | £78,000 – £98,500 | £98,000 – £126,000 |
Want a range for your exact size? The guide-price tool takes about a minute.
Extensions in and around Brentwood
Our survey diary covers Brentwood, including CM13, CM14, CM15. Nearby, we also take on projects in Billericay (5 miles), Basildon (7 miles), South Ockendon (8 miles), Stanford-le-Hope (9 miles).
For homes towards Greater London, Hornchurch is around 6 miles away. The East of England mixes market-town terraces, inter-war semis and modern estates. Clay soils are common in parts of the region, which can affect foundation design.
Our process, step by step
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
It starts with a visit to your house to measure, check access and talk through ideas and budget.
Design and approvals
Once the layout is agreed, we deal with the council: planning permission or written confirmation that none is needed, plus building control.
Fixed written price
The price is fixed in writing once the design is settled, with a clear programme and payment stages.
Build and sign-off
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Wraparound extension questions answered
Do you cover all of Brentwood?
Yes. We cover Brentwood and the surrounding parts of Essex. Site visits are free and there is no obligation.
Do I need building regulations approval in Brentwood?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
How long does a wraparound extension take to build in Brentwood?
On site, typically 14 to 20 weeks once approvals are in place. Before that, allow 8–16 weeks design and approvals.
How much does a wraparound extension cost?
Our guide range is about £2,120 to £3,920 per m² including VAT. A 25 m² standard-spec wraparound typically lands around £60,500 to £77,000 in Brentwood before design and council fees.
Do wraparound extensions need planning permission?
Usually, yes. In England the side element counts as a side extension and the rear element as a rear extension, and the combination normally falls outside permitted development. A householder application costs £548 in England from 1 April 2026.
Book a free site visit in Brentwood
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.