Weston-super-Mare · Somerset

Two-storey side extensions in Weston-super-Mare

A two-storey side extension is one of the most space-efficient ways to add bedrooms and living space to a house in Weston-super-Mare, because the new floors share one set of foundations and one roof.

Quick reference for homeowners in Weston-super-Mare.

Postcode districts
BS22, BS23, BS24 and BS29
County / area
Somerset, England
Price region
South West 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
Yatton (7.2 miles), Burnham-on-Sea (7.5 miles), Clevedon (8.4 miles)
Distance to Bath
about 26.6 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.

Weston-super-Mare sits about 26.6 miles from Bath. Closer to home, Yatton is 7.2 miles away and Burnham-on-Sea 7.5 miles.

What it costs in Weston-super-Mare

Most of the cost of a two-storey side extension is set by its size and specification. For Weston-super-Mare and the rest of South West England, our guide is £2,110–£2,830 per m² including VAT, so about £88,500–£119,000 for a 3 m × 7 m footprint on two floors (42 m² of new floor space). Steelwork for wide openings is the item most likely to move the figure; we'll know once the engineer has designed it.

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 Weston-super-Mare

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 Weston-super-Mare homes

Matching the ridge and roof

A hipped house usually needs a hipped extension roof, and a gabled house a gable. Matching the pitch, tiles, ridge detail and brick bond is what makes a side extension look original rather than added, and councils look closely at it on a front-facing addition.

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.

How we'd run your project

  1. Start at your house

    We come to your home in Weston-super-Mare, measure up, check the ground floor walls and roof structure, and note anything near the boundaries.

  2. Drawings, then consent

    We draw the scheme, check it against the rules in England, and take it through the right consent with the council.

  3. Detail and price

    Construction drawings, engineer's calculations and building control sign-off, then a written fixed price for the build.

  4. Build it

    The new structure goes up first, then we open into the house, finish inside and get the completion certificate.

Questions about two-storey side extensions in Weston-super-Mare

Which postcodes do you cover around Weston-super-Mare?

We cover Weston-super-Mare (BS22, BS23, BS24 and BS29) and nearby places including Yatton, Burnham-on-Sea and Clevedon, plus the rest of Somerset. The first site visit is free.

Who handles building regulations for a project in Weston-super-Mare?

We handle it as part of the project. What's needed in England: building regulations approval (full plans recommended) from the council or a registered building control approver, with a completion certificate at the end. We prepare the drawings and the engineer's calculations, book the inspections and pass you the completion paperwork at the end.

How much does a two-storey side extension cost in Weston-super-Mare?

Our guide for South West England, which covers Weston-super-Mare, 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.

Do I need planning permission for a two-storey side extension in Weston-super-Mare?

Weston-super-Mare 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.

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

We also cover places near Weston-super-Mare, including:

Other extensions in Weston-super-Mare

All two-storey extension services in Weston-super-Mare · Two-storey side extensions across Somerset

The quickest next step is a visit. We'll look at your house in Weston-super-Mare and give you an honest view of the options.

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