Bognor Regis · West Sussex

Extra bedroom and en-suite extensions in Bognor Regis

Adding an extra bedroom and en-suite extension in Bognor Regis gives you two new rooms stacked on one footprint. Here's how we'd approach it, what it typically costs and the rules that apply in England.

Quick reference for homeowners in Bognor Regis.

Postcode districts
PO21 and PO22
County / area
West Sussex, England
Price region
South East England
Guide price
£61,500–£83,000 (£2,200–£2,970 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
Barnham (3.9 miles), Westergate (4 miles), Chichester (5.8 miles)
Distance to Crawley
about 31.5 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 PO21 and PO22 in and around Bognor Regis, along with neighbouring Barnham, Westergate and Chichester.

What it costs in Bognor Regis

Our guide for South East England is £2,200–£2,970 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 Bognor Regis at roughly £61,500–£83,000 (plus £5,500–£11,000 for the en-suite). We'll give you a written design-stage price first, then a fixed build price once the drawings are agreed.

SpecPer m²A 4 m × 3.5 m footprint on two floors (28 m² of new floor space)
Essential£2,020–£2,730 per m²£56,500–£76,500
Standard£2,200–£2,970 per m²£61,500–£83,000
Premium£2,640–£3,560 per m²£74,000–£100,000

Planning and building regulations in Bognor Regis

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 Bognor Regis 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.

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.

How we'd run your project

  1. Visit and first ideas

    One of our team visits your house in Bognor Regis, checks the walls, roof and drains, and sketches out options with you.

  2. Plans, then approval

    Measured survey, design, then the right approval route for your house. We explain each step before we take it.

  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 Bognor Regis

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.

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

Bognor Regis 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.

Which postcodes do you cover around Bognor Regis?

We cover Bognor Regis (PO21 and PO22) and nearby places including Barnham, Westergate and Chichester, plus the rest of West Sussex. 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

The same service in neighbouring towns:

Other extensions in Bognor Regis

All two-storey extension services in Bognor Regis · Extra bedroom and en-suite extensions across West Sussex

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

CallGuide price