Extra bedroom and en-suite extensions in Chelmsley Wood

Quick reference for homeowners in Chelmsley Wood.

Postcode districts: B33, B37 and B40
County / area: West Midlands, England
Price region: West Midlands
Guide price: £56,000–£75,500 (£2,000–£2,700 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: Castle Vale (3.7 miles), Acocks Green (3.8 miles), Washwood Heath (4 miles)
Distance to Birmingham: about 6.8 miles
First visit: Free, no obligation

About an extra bedroom and en-suite extension

An extra bedroom and en-suite extension is a two-storey extension planned around a new double bedroom with its own shower room on the first floor, with a ground-floor room below. It is one of the most effective ways to add space for a growing family. Nationwide's 2025 research linked adding a double bedroom and bathroom to a three-bed, one-bathroom house with value gains of up to 24%.

We cover postcode districts B33, B37 and B40 in and around Chelmsley Wood, along with neighbouring Castle Vale, Acocks Green and Washwood Heath.

What it costs in Chelmsley Wood

In the West Midlands, which includes Chelmsley Wood, we'd expect an extra bedroom and en-suite extension to cost around £56,000–£75,500 (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), or £2,000–£2,700 per m² including VAT. 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	£1,840–£2,480 per m²	£51,500–£69,500
Standard	£2,000–£2,700 per m²	£56,000–£75,500
Premium	£2,400–£3,240 per m²	£67,000–£90,500

Planning and building regulations in Chelmsley Wood

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 Chelmsley Wood homes

Sound and privacy

Bedrooms above a kitchen or family room benefit from an insulated floor to reduce noise. Side-facing upstairs windows usually have to be obscure-glazed, so we place the main bedroom window to the rear and the en-suite window to the side where possible.

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 Chelmsley Wood, checks the walls, roof and drains, and sketches out options with you.
Get it approved
Once you're happy with the design we submit it to the council for Chelmsley Wood and deal with any questions from the planning officer.
Technical design
We prepare the building regulations drawings, structural calculations and specification so the build price can be fixed.
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 Chelmsley Wood

Do I need planning permission for an extra bedroom and en-suite extension in Chelmsley Wood?

Chelmsley Wood 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.

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.

Which postcodes do you cover around Chelmsley Wood?

We cover Chelmsley Wood (B33, B37 and B40) and nearby places including Castle Vale, Acocks Green and Washwood Heath, plus the rest of the West Midlands. The first site visit is free.

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.

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.

Nearby

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Other extensions in Chelmsley Wood

All two-storey extension services in Chelmsley Wood · Extra bedroom and en-suite extensions across the West Midlands

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