Extra bedroom and en-suite extensions in Oakwood (Derbyshire)
An extra bedroom and en-suite extension is one of the most space-efficient ways to add bedrooms and living space to a house in Oakwood (Derbyshire), because the new floors share one set of foundations and one roof.
Before you start in Oakwood (Derbyshire), here's what applies.
- Postcode districts
- DE21
- County / area
- Derbyshire, England
- Price region
- East Midlands
- Guide price
- £55,000–£74,000 (£1,960–£2,650 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
- Chaddesden (1 mile), Derby (2.4 miles), Sinfin (4.9 miles)
- Distance to Derby
- about 2.4 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 Oakwood (Derbyshire) (DE21) and the places around it, including Chaddesden (1.0 miles), Derby (2.4 miles) and Sinfin.
What it costs in Oakwood (Derbyshire)
Our guide for the East Midlands is £1,960–£2,650 per m² including VAT. On a project with a 4 m × 3.5 m footprint on two floors (28 m² of new floor space), that puts an extra bedroom and en-suite extension in Oakwood (Derbyshire) at roughly £55,000–£74,000 (plus £5,500–£11,000 for the en-suite). Design fees, structural calculations and approval fees are separate and listed on our prices page.
| Spec | Per m² | A 4 m × 3.5 m footprint on two floors (28 m² of new floor space) |
|---|---|---|
| Essential | £1,800–£2,430 per m² | £50,500–£68,000 |
| Standard | £1,960–£2,650 per m² | £55,000–£74,000 |
| Premium | £2,350–£3,180 per m² | £66,000–£89,000 |
Planning and building regulations in Oakwood (Derbyshire)
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 Oakwood (Derbyshire) 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
Start at your house
We come to your home in Oakwood (Derbyshire), measure up, check the ground floor walls and roof structure, and note anything near the boundaries.
Choose the approval route
Some designs fit permitted development, most need a householder application. We decide which applies in England before drawing in detail.
Structure and building control
A structural engineer sizes the foundations and steels, and we get building regulations approval before work starts.
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 Oakwood (Derbyshire)
How much does an extra bedroom and en-suite extension cost in Oakwood (Derbyshire)?
Our guide for the East Midlands, which covers Oakwood (Derbyshire), is £1,960–£2,650 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 £55,000–£74,000 (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.
Do I need planning permission for an extra bedroom and en-suite extension in Oakwood (Derbyshire)?
Oakwood (Derbyshire) 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.
How big should a new double bedroom be?
There is no legal minimum size for a bedroom in a house you own, so the test is whether it works. A comfortable double needs room for the bed with space to walk round it, wardrobes and a door that opens freely. We draw furniture on the plans so you can judge the space before anything is built.
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
Nearby towns we cover for extra bedroom and en-suite extensions:
Other extensions in Oakwood (Derbyshire)
All two-storey extension services in Oakwood (Derbyshire) · Extra bedroom and en-suite extensions across Derbyshire
Tell us about your house in Oakwood (Derbyshire) and we'll call you back to arrange a free, no-obligation visit.