Annexe extensions across Southend-on-Sea
If you live in Southend-on-Sea and want more space without moving, an annexe extension is one of the most practical ways to get it. We handle the drawings, approvals and the build.
- Guide price in Southend-on-SeaFrom £58,000 inc VAT
- PlanningUsually a householder application
- Build time16–24 weeks on site
- Postcode districtsSS0, SS1, SS2, SS3, SS4
Extensions in and around Southend-on-Sea
Postcode districts we cover around Southend-on-Sea include SS0, SS1, SS2, SS3, SS4, SS9. We also work in nearby Hadleigh (5 miles), Rayleigh (6 miles), Canvey Island (6 miles), Benfleet (7 miles).
Gillingham, in Kent, is roughly 13 miles from Southend-on-Sea and also on our list. Across the East of England many houses sit on generous plots, and single-storey and wraparound extensions are a natural fit.
Guide prices for Southend-on-Sea
Labour and material costs vary across the UK, so for Southend-on-Sea we use our East of England factor (×1.06). The ranges include VAT and exclude design, structural and council fees.
Typical rates in Southend-on-Sea: £2,120 to £4,030 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| Studio annexe 25 m² | £58,000 – £73,000 | £63,500 – £79,500 | £79,500 – £101,000 |
| One-bedroom annexe 35 m² | £74,000 – £93,000 | £89,000 – £111,500 | £111,000 – £141,000 |
| Larger annexe 45 m² | £95,000 – £119,500 | £114,000 – £143,500 | £143,000 – £181,500 |
For a figure based on your own dimensions, use our guide-price tool.
Who an annexe extension suits
- Homes with a large side or rear garden
- Multi-generational families
- Relatives who need support close by
Accessibility is cheaper to design in than to retrofit. Level access, a 900 mm door width, a level-access shower and space to turn a wheelchair can all be planned into the footprint for little extra cost.
Will the council need to approve it?
In England an annexe that stays part of the household and connects to the house is assessed as an extension, but its size usually takes it beyond permitted development, so a householder application describing the ancillary use is the normal route.
Before any drawing is finalised we check whether the house is listed, in a conservation area or subject to an Article 4 direction.
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.
Applications are decided by the local planning authority (your district, borough or unitary council).
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
A designer visits, takes measurements and photos, and discusses layouts, budget and timing with you.
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
With the design and specification agreed, you get a fixed written price and a start date.
Build and sign-off
We build it with one project manager, book the building control inspections and hand over the completion certificate.
Common questions in Southend-on-Sea
Can I see a price before committing to anything?
Yes. The guide prices on this page are adjusted for Southend-on-Sea, 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 I need building regulations approval in Southend-on-Sea?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
Who do I contract with for an annexe extension in Southend-on-Sea?
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.
Will an annexe affect council tax?
It can. Some annexes are assessed separately for council tax, with discounts or exemptions in some cases when occupied by a relative. Check with the Valuation Office Agency (England and Wales), your local assessor (Scotland) or Land & Property Services (Northern Ireland).
Does an annexe extension need planning permission?
Usually yes, because of its size and the way it will be used. Councils check that it stays ancillary to the main house, so the application must describe the use clearly.
Book a free site visit in Southend-on-Sea
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.