Two-storey side extensions in Bexhill-on-Sea

Before you start in Bexhill-on-Sea, here's what applies.

Postcode districts: TN33, TN39 and TN40
County / area: East Sussex, England
Price region: South East England
Guide price: £94,500–£127,000 (£2,260–£3,030 per m²)
Approval route: Planning permission is needed: in England, permitted development only allows single-storey extensions to the side.
Nearest towns: St Leonards-on-Sea (3.3 miles), Hastings (4.8 miles), Hailsham (9.3 miles)
Distance to Brighton: about 26.7 miles
First visit: Free, no obligation

About a two-storey side extension

A two-storey side extension suits a detached or semi-detached house with a side garden, driveway or garage wide enough to build on. You get a design that sits comfortably on the street, a planning application or permitted development check depending on your nation, structural design, building regulations approval and the build itself. We manage the whole process, and the work is carried out by vetted teams working under S&K.

We cover Bexhill-on-Sea (TN33, TN39 and TN40) and the places around it, including St Leonards-on-Sea (3.3 miles), Hastings (4.8 miles) and Hailsham.

What it costs in Bexhill-on-Sea

Guide prices for two-storey side extensions in South East England are around £2,260–£3,030 per m² of new floor space, including VAT. For a typical project with a 3 m × 7 m footprint on two floors (42 m² of new floor space), that's roughly £94,500–£127,000. These are guides, not quotes. Ground conditions, steelwork and access can move the figure either way.

Spec	Per m²	A 3 m × 7 m footprint on two floors (42 m² of new floor space)
Essential	£2,070–£2,780 per m²	£87,000–£117,000
Standard	£2,260–£3,030 per m²	£94,500–£127,000
Premium	£2,710–£3,630 per m²	£113,500–£152,500

Planning and building regulations in Bexhill-on-Sea

In England, a two-storey side extension always needs householder planning permission, because permitted development only allows single-storey extensions beyond a side wall. The fee is £548 (or £575 for applications made from 8 December 2026), and councils should decide within 8 weeks of validation. Expect them to look at set-back, roof height, gaps to the boundary and the effect on neighbours.

Approval in England: Householder planning application: £548 (or £575 for applications made from 8 December 2026). Lawful development certificate: £274 (about £288 for applications from 8 December 2026). Councils should decide householder applications within 8 weeks of validation.

Building regulations: Building regulations approval (full plans recommended) from the council or a registered building control approver, with a completion certificate at the end.

Design points for Bexhill-on-Sea homes

Set-down and set-back

Councils usually want a two-storey side extension to look subordinate to the house. Setting the front wall back from the main front and dropping the ridge slightly below the main roof helps it read as an addition, and is often expected in local design guidance.

Access and services

Side extensions often cover the only route to the back garden, a gas meter, soil pipes or a drain run. We plan bin and bike access, move meters and pipes where needed and check drains early, because these items affect both cost and layout.

How we'd run your project

Measure and listen
A visit to Bexhill-on-Sea to understand how you live in the house now and what the extra rooms need to do, plus a first look at the structure.
Drawings, then consent
We draw the scheme, check it against the rules in England, and take it through the right consent with the council.
Fixed price in writing
With approved drawings and calculations, we give you a fixed build price and a programme you can plan around.
Finish and certify
Second fix, plastering and making good, then building control's final inspection and the completion paperwork.

Questions about two-storey side extensions in Bexhill-on-Sea

Which postcodes do you cover around Bexhill-on-Sea?

We cover Bexhill-on-Sea (TN33, TN39 and TN40) and nearby places including St Leonards-on-Sea, Hastings and Hailsham, plus the rest of East Sussex. The first site visit is free.

How much does a two-storey side extension cost in Bexhill-on-Sea?

Our guide for South East England, which covers Bexhill-on-Sea, is £2,260–£3,030 per m² including VAT. A typical project with a 3 m × 7 m footprint on two floors (42 m² of new floor space) comes to about £94,500–£127,000. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.

Do I need planning permission for a two-storey side extension in Bexhill-on-Sea?

Bexhill-on-Sea is in England, so England planning rules apply. Planning permission is needed: in England, permitted development only allows single-storey extensions to the side. If in doubt, a lawful development certificate or a planning application gives you certainty before you build.

How long does a two-storey side extension take?

Allow 4 to 8 weeks for survey and design, then the approval period (councils should decide householder applications within 8 weeks of validation), then 4 to 8 weeks of technical design, which can overlap. The build itself usually takes 14 to 20 weeks, longer for large or complex designs.

Can I build a two-storey side extension over my driveway?

Yes, if the drive is wide enough for a useful room and the council accepts the design. You may lose off-road parking, which some councils weigh up, and the foundations need to suit the ground below. We check parking, drains and meter positions at the free site visit before any drawings are prepared.

Nearby

Close to Bexhill-on-Sea? We work across the area, including:

Other extensions in Bexhill-on-Sea

All two-storey extension services in Bexhill-on-Sea · Two-storey side extensions across East Sussex

Ready to talk it through? Call us or send the form and we'll arrange a visit to your home in Bexhill-on-Sea.