Extra bedroom and en-suite extensions in Weston-super-Mare
If you live in Weston-super-Mare and need more room without moving, an extra bedroom and en-suite extension is worth a serious look. We handle the drawings, approvals, structure and build.
Useful details for planning an extra bedroom and en-suite extension in Weston-super-Mare.
- Postcode districts
- BS22, BS23, BS24 and BS29
- County / area
- Somerset, England
- Price region
- South West England
- Guide price
- £57,500–£78,000 (£2,060–£2,780 per m²), plus £5,500–£11,000 for the en-suite
- 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
- 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 an extra bedroom and en-suite extension
This service suits you if you need another bedroom, or want a main bedroom with its own bathroom, without converting the loft or moving. You get a first-floor layout that connects well to your landing, an en-suite designed for plumbing and ventilation, a useful room downstairs, the approvals your nation needs and the build, managed by us and carried out by vetted teams working under S&K.
Around Weston-super-Mare we also work in Yatton, Burnham-on-Sea and Clevedon, and across the rest of Somerset. Postcode districts in and near Weston-super-Mare: BS22, BS23, BS24 and BS29.
What it costs in Weston-super-Mare
Guide prices for extra bedroom and en-suite 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 (plus £5,500–£11,000 for the en-suite). The fastest way to a firmer number is a free site visit, after which we price the design stage in writing.
| 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 Weston-super-Mare
In England, an extra bedroom extension at the rear can be permitted development if it goes no more than 3 m beyond the original rear wall and stays 7 m from the rear boundary. Upper side windows, including en-suite windows, must be obscure-glazed and non-opening below 1.7 m. Side or deeper designs need planning permission, costing £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 Weston-super-Mare homes
Planning the en-suite
An en-suite needs a route for the soil pipe to the drains, enough fall for waste water and an extract fan to the outside under Part F. Placing it over the ground-floor utility or near an existing drain keeps pipework short and hidden.
Connecting to the landing
The new bedroom must be reached from the existing landing, usually through a new opening in the outside wall or by taking part of an existing bedroom as a corridor. We look at the stairs and landing first, because a poor connection can waste much of the new space.
How we'd run your project
Visit and first ideas
One of our team visits your house in Weston-super-Mare, checks the walls, roof and drains, and sketches out options with you.
Drawings and permission
Our designers produce plans and elevations, then we take care of planning or permitted development checks with the council covering Weston-super-Mare.
Technical design
We prepare the building regulations drawings, structural calculations and specification so the build price can be fixed.
Build
Foundations, walls, floor, roof, windows, then first and second fix. We break through into the house as late as we can.
Questions about extra bedroom and en-suite 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.
How much does an extra bedroom and en-suite extension cost in Weston-super-Mare?
Our guide for South West England, which covers Weston-super-Mare, is £2,060–£2,780 per m² including VAT. A typical project with a 4 m × 3.5 m footprint on two floors (28 m² of new floor space) comes to about £57,500–£78,000 (plus £5,500–£11,000 for the en-suite). Design and approval fees are extra, and we fix the build price in writing once the design is agreed.
How long does an extra bedroom and en-suite 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 an en-suite go in a room with no window?
Yes. A shower room without a window is allowed, provided it has a mechanical extract fan to the outside that meets Part F. Many people prefer a window for daylight, but if it faces a neighbour it will usually need obscure glass. We plan the extract route early so the duct is hidden.
Does an extra bedroom add value to my house?
It usually does, though not always by the full cost. Nationwide's 2025 research found that adding a double bedroom to a two-bed house was linked to about 13% higher value, and a double bedroom and bathroom on a three-bed, one-bathroom house up to 24%. Local ceiling prices still apply.
Nearby
Close to Weston-super-Mare? We work across the area, including:
Other extensions in Weston-super-Mare
All two-storey extension services in Weston-super-Mare · Extra bedroom and en-suite extensions across Somerset
Book a free site visit in Weston-super-Mare and we'll tell you what's possible, what approvals you need and what the design stage would cost.