Double-storey extensions for homes in Hadleigh
Hadleigh homeowners can use us for the whole double-storey extension project: survey, design, planning or permitted development checks, building regulations and the build itself.
- Guide price in HadleighFrom £40,000 inc VAT
- PlanningUsually a householder application
- Build time16–24 weeks on site
- Postcode districtsSS7, SS9
Covering Hadleigh
Our survey diary covers Hadleigh, including SS7, SS9. Neighbouring towns we cover include Benfleet (2 miles), Rayleigh (2 miles), Canvey Island (2 miles), Southend-on-Sea (5 miles).
Across the East of England many houses sit on generous plots, and single-storey and wraparound extensions are a natural fit.
What should I budget for a double-storey extension in Hadleigh?
These guide figures apply our East of England adjustment (×1.06) to national rates. They include VAT at 20% and cover the build itself; design and council fees are listed separately.
Typical rates in Hadleigh: £1,640 to £3,180 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 4 m, two floors 24 m² | £40,000 – £48,500 | £45,500 – £60,000 | £58,500 – £76,500 |
| 4 m × 4 m, two floors 32 m² | £52,500 – £63,000 | £61,000 – £80,000 | £78,000 – £102,000 |
| 4 m × 6 m, two floors 48 m² | £78,500 – £94,500 | £91,500 – £120,000 | £117,000 – £153,000 |
Try the guide-price tool to see a range for your own size and finish.
What we take care of
- Measured survey, design and planning drawings
- Insulation, plastering, electrics and plumbing to finish
- Foundations sized for two floors
- Building regulations drawings and structural design
- Ground and first floor structure, roof tied into the existing roof
- Breaking through at both levels, stairs and landing changes where needed
Planning rules that apply in Hadleigh
In England a two-storey rear extension is permitted development only if it projects no more than 3 m from the original rear wall, sits at least 7 m from the rear boundary, matches the roof pitch and uses obscure, non-opening side windows upstairs. Most two-storey extensions therefore go through a householder planning application, which costs £548 from 1 April 2026 and normally takes about 8 weeks.
The planning position for a specific Hadleigh address depends on its history and any designations, which is why we check it at the first visit.
If the work involves a shared wall, building on the boundary, or digging foundations within 3 m (sometimes 6 m) of a neighbour's building, the Party Wall etc. Act 1996 applies and notice must be served before work starts: two months for work to a party wall, one month for new walls on the boundary and for excavations.
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.
Applications are decided by the local planning authority (your district, borough or unitary council).
What happens next
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
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
Design and approvals
Drawings are prepared and agreed with you, then submitted for the right planning route and building regulations approval.
Fixed written price
We confirm the build price in writing, based on the approved drawings and the finishes you have chosen.
Build and sign-off
We build it with one project manager, book the building control inspections and hand over the completion certificate.
Your questions about a double-storey extension in Hadleigh
Who do I contract with for a double-storey extension in Hadleigh?
Your contract is with S&K Property Investments and Improvement Ltd, which designs and manages the project and the build teams who carry it out.
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Hadleigh, and the guide-price tool gives a range for your own size. After the survey you get a written price before anything is agreed.
Do you cover all of Hadleigh?
Yes. We cover Hadleigh and the surrounding parts of Essex. Site visits are free and there is no obligation.
Does a double-storey extension need planning permission?
Often, yes. In England a two-storey rear extension can be permitted development only if it projects no more than 3 m and sits at least 7 m from the rear boundary, with matching roof pitch and obscure side windows. Side extensions over one storey always need planning permission. We confirm the route at the survey.
Do I need a Party Wall Agreement?
If you are in England or Wales and the work involves a shared wall or digging foundations close to a neighbour, the Party Wall etc. Act 1996 applies and notices must be served before work starts. We tell you which notices are needed.
Book a free site visit in Hadleigh
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.