South Benfleet · Essex

Two-storey side extensions in South Benfleet

Adding a two-storey side extension in South Benfleet gives you two new rooms stacked on one footprint. Here's how we'd approach it, what it typically costs and the rules that apply in England.

Useful details for planning a two-storey side extension in South Benfleet.

Postcode districts
SS7
County / area
Essex, England
Price region
East of England
Guide price
£88,500–£119,000 (£2,110–£2,830 per m²)
Approval route
Planning permission is needed: in England, permitted development only allows single-storey extensions to the side.
Nearest towns
Hadleigh (2.2 miles), Pitsea (2.3 miles), Canvey Island (2.3 miles)
Distance to Southend-on-Sea
about 6.7 miles
First visit
Free, no obligation

About a two-storey side extension

A two-storey side extension is a new two-floor addition built into the space beside your house, often over a driveway or side passage. It typically adds one or two bedrooms upstairs and a utility, study or larger kitchen below, without giving up rear garden.

Around South Benfleet we also work in Hadleigh, Pitsea and Canvey Island, and across the rest of Essex. Postcode district in and near South Benfleet: SS7.

What it costs in South Benfleet

For budgeting in South Benfleet, allow around £88,500–£119,000 for a two-storey side extension with a 3 m × 7 m footprint on two floors (42 m² of new floor space). That's based on £2,110–£2,830 per m² including VAT for the East of England. These are guides, not quotes. Ground conditions, steelwork and access can move the figure either way.

SpecPer m²A 3 m × 7 m footprint on two floors (42 m² of new floor space)
Essential£1,940–£2,610 per m²£81,500–£109,500
Standard£2,110–£2,830 per m²£88,500–£119,000
Premium£2,530–£3,400 per m²£106,500–£143,000

Planning and building regulations in South Benfleet

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 South Benfleet homes

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.

Side windows, boundaries and gutters

Upstairs windows in the side wall face the neighbour, so they are usually obscure-glazed and fixed, or left out. Building close to the boundary also raises questions about foundations, overhanging gutters and access for maintenance, so we design the eaves and gutter to stay within your land.

How we'd run your project

  1. Free site visit

    We visit your home in South Benfleet, look at the structure, access and boundaries, and talk through what you want the new rooms to do.

  2. Design and approvals

    We draw the extension and check it against the rules for England, then apply for planning permission or a certificate of lawfulness, whichever fits.

  3. Fixed price in writing

    With approved drawings and calculations, we give you a fixed build price and a programme you can plan around.

  4. 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 South Benfleet

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.

Which postcodes do you cover around South Benfleet?

We cover South Benfleet (SS7) and nearby places including Hadleigh, Pitsea and Canvey Island, plus the rest of Essex. The first site visit is free.

Do I need planning permission for a two-storey side extension in South Benfleet?

South Benfleet 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 much does a two-storey side extension cost in South Benfleet?

Our guide for the East of England, which covers South Benfleet, is £2,110–£2,830 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 £88,500–£119,000. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.

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

The same service in neighbouring towns:

Other extensions in South Benfleet

All two-storey extension services in South Benfleet · Two-storey side extensions across Essex

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