Yatton · Somerset

Two-storey side extensions in Yatton

Adding a two-storey side extension in Yatton 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.

What we'd confirm first for a project in Yatton.

Postcode districts
BS25 and BS49
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
Clevedon (4 miles), Nailsea (4.1 miles), Portishead (6.9 miles)
Distance to Bath
about 19.9 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.

We cover postcode districts BS25 and BS49 in and around Yatton, along with neighbouring Clevedon, Nailsea and Portishead.

What it costs in Yatton

In South West England, which includes Yatton, we'd expect a two-storey side extension to cost around £88,500–£119,000 for a 3 m × 7 m footprint on two floors (42 m² of new floor space), or £2,110–£2,830 per m² including VAT. We'll give you a written design-stage price first, then a fixed build price once the drawings are agreed.

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 Yatton

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 Yatton 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.

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

  1. Look at the house

    We start in Yatton with a free visit: measurements, photos, a look at the loft and drains, and a frank chat about budget.

  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. Engineer it

    Foundations sized for two floors, steels for any openings, and building control approval, all before anyone starts on site.

  4. Build

    Foundations, walls, floor, roof, windows, then first and second fix. We break through into the house as late as we can.

Questions about two-storey side extensions in Yatton

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.

How much does a two-storey side extension cost in Yatton?

Our guide for South West England, which covers Yatton, 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.

Who handles building regulations for a project in Yatton?

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.

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

Yatton 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

Close to Yatton? We work across the area, including:

Other extensions in Yatton

All two-storey extension services in Yatton · Two-storey side extensions across Somerset

Send us your postcode and a few details. We'll get back to you to arrange a visit and talk through your options.

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