Two-storey rear extensions in Yeovil

Yeovil: the key facts for this kind of project.

Postcode districts: BA20, BA21, BA22, TA12, TA13, TA14 and nearby districts
County / area: Somerset, England
Price region: South West England
Guide price: £57,500–£78,000 (£2,060–£2,780 per m²)
Approval route: It may be permitted development if it goes no more than 3 m beyond the original rear wall (counting any single-storey part) and stays 7 m from the rear boundary; otherwise it needs planning permission.
Nearest towns: Sherborne (5 miles), Street (13.5 miles), Chard (15.3 miles)
Distance to Bath: about 32.2 miles
First visit: Free, no obligation

About a two-storey rear extension

A two-storey rear extension suits you if you need more room on both floors and have a reasonably deep garden. You get one team for the whole job: a measured survey, the design, a check on whether permitted development applies, planning drawings where they are needed, structural design, building regulations approval and the build itself, carried out by vetted teams working under S&K. Every project starts with a free site visit.

Yeovil sits about 32.2 miles from Bath. Closer to home, Sherborne is 5.0 miles away and Street 13.5 miles.

What it costs in Yeovil

Guide prices for two-storey rear extensions in South West England are around £2,060–£2,780 per m² of new floor space, including VAT. For a typical project with a 4 m × 3.5 m footprint on two floors (28 m² of new floor space), that's roughly £57,500–£78,000. We'll give you a written design-stage price first, then a fixed build price once the drawings are agreed.

Spec	Per m²	A 4 m × 3.5 m footprint on two floors (28 m² of new floor space)
Essential	£1,900–£2,560 per m²	£53,000–£71,500
Standard	£2,060–£2,780 per m²	£57,500–£78,000
Premium	£2,470–£3,340 per m²	£69,000–£93,500

Planning and building regulations in Yeovil

In England, a two-storey rear extension can be permitted development if it goes no more than 3 m beyond the rear wall of the original house, stays at least 7 m from the rear boundary and matches the house's materials and roof pitch. It is not permitted development in conservation areas, National Landscapes, National Parks, World Heritage Sites or the Broads. Otherwise a householder application costs £548 (or £575 for applications made from 8 December 2026).

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 Yeovil homes

Depth and neighbours' light

Councils check that a two-storey rear extension does not take too much light or outlook from neighbouring windows, and many use a 45-degree line drawn from the nearest habitable window. We test this at sketch stage, so the depth you are shown is one that can realistically be approved.

Upstairs layout and windows

Bedrooms above need a window big enough for escape or a protected route to the stairs. Side-facing upstairs windows normally have to be obscure-glazed and fixed below 1.7 m, so we put the main bedroom windows in the rear wall and use roof lights where extra daylight is needed.

How we'd run your project

Start at your house
We come to your home in Yeovil, measure up, check the ground floor walls and roof structure, and note anything near the boundaries.
Plans, then approval
Measured survey, design, then the right approval route for your house. We explain each step before we take it.
Engineer it
Foundations sized for two floors, steels for any openings, and building control approval, all before anyone starts on site.
Build and hand over
We manage the build from groundworks to decoration-ready finish and hand over with the completion paperwork.

Questions about two-storey rear extensions in Yeovil

How long does a two-storey rear 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.

Do I need planning permission for a two-storey rear extension in Yeovil?

Yeovil is in England, so England planning rules apply. It may be permitted development if it goes no more than 3 m beyond the original rear wall (counting any single-storey part) and stays 7 m from the rear boundary; otherwise it needs planning permission. If in doubt, a lawful development certificate or a planning application gives you certainty before you build.

Who handles building regulations for a project in Yeovil?

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.

Can I have a balcony on a two-storey rear extension?

In England, balconies, verandas and raised platforms are not permitted development, so a balcony on a two-storey rear extension needs planning permission. A Juliet balcony, a guard rail across full-height doors with no platform to stand on, is often a practical alternative, but it still needs checking against the rules and the council's approach to overlooking.

Will a two-storey rear extension block my neighbour's light?

It can if it is too deep or too close to the boundary, which is why councils look closely at its effect on neighbouring windows and gardens. We test the design against light and outlook early, keep the first floor shorter or set in where needed, and use a hipped roof to reduce bulk on the boundary side.

Nearby

Nearby towns we cover for two-storey rear extensions:

Other extensions in Yeovil

All two-storey extension services in Yeovil · Two-storey rear extensions across Somerset

Book a free site visit in Yeovil and we'll tell you what's possible, what approvals you need and what the design stage would cost.