Wilmslow · Cheshire

Extra bedroom and en-suite extensions in Wilmslow

We plan and build extra bedroom and en-suite extensions for homeowners in Wilmslow and nearby. Every project starts with a free visit and a design stage priced in writing before any work begins.

The basics for Wilmslow at a glance.

Postcode districts
SK9
County / area
Cheshire, England
Price region
North West England
Guide price
£53,000–£72,000 (£1,900–£2,560 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
Bramhall (3.4 miles), Cheadle Hulme (3.7 miles), Hale Barns (4.4 miles)
Distance to Warrington
about 15.1 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.

We cover postcode district SK9 in and around Wilmslow, along with neighbouring Bramhall, Cheadle Hulme and Hale Barns.

What it costs in Wilmslow

Most of the cost of an extra bedroom and en-suite extension is set by its size and specification. For Wilmslow and the rest of North West England, our guide is £1,900–£2,560 per m² including VAT, so about £53,000–£72,000 (plus £5,500–£11,000 for the en-suite) for a 4 m × 3.5 m footprint on two floors (28 m² of new floor space). Kitchens, bathroom fittings and flooring are priced separately so you can compare like with like.

SpecPer m²A 4 m × 3.5 m footprint on two floors (28 m² of new floor space)
Essential£1,750–£2,360 per m²£49,000–£66,000
Standard£1,900–£2,560 per m²£53,000–£72,000
Premium£2,280–£3,080 per m²£64,000–£86,000

Planning and building regulations in Wilmslow

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 Wilmslow homes

Escape window and fire safety

A new first-floor bedroom needs an escape window with a clear opening of at least 0.33 m², at least 450 mm wide and high, and the bottom no more than 1,100 mm above the floor, unless there is a protected route to the stairs. We design the windows to meet this.

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

  1. Look at the house

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

  2. Drawings and permission

    Our designers produce plans and elevations, then we take care of planning or permitted development checks with the council covering Wilmslow.

  3. Engineer it

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

  4. Build it

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

Questions about extra bedroom and en-suite extensions in Wilmslow

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.

Who handles building regulations for a project in Wilmslow?

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 an extra bedroom and en-suite extension in Wilmslow?

Wilmslow 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.

What goes on the ground floor below a new bedroom?

Whatever suits you: a bigger kitchen, a family room, a study, a utility or a downstairs shower room. The ground floor usually costs about the same whatever it is used for, apart from kitchen units and bathroom fittings, which are priced separately.

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

We also cover places near Wilmslow, including:

Other extensions in Wilmslow

All two-storey extension services in Wilmslow · Extra bedroom and en-suite extensions across Cheshire

Tell us about your house in Wilmslow and we'll call you back to arrange a free, no-obligation visit.

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