Emsworth · West Sussex

Extra bedroom and en-suite extensions in Emsworth

For an extra bedroom and en-suite extension in Emsworth, the first questions are always the same: how big, which approvals, and what it will cost. This page answers all three for West Sussex.

Emsworth: the key facts for this kind of project.

Postcode districts
PO10
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
Havant (2.2 miles), South Hayling (4.5 miles), Hayling Island (4.6 miles)
Distance to Crawley
about 37.6 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.

We cover Emsworth (PO10) and the places around it, including Havant (2.2 miles), South Hayling (4.5 miles) and Hayling Island.

What it costs in Emsworth

In South East England, which includes Emsworth, we'd expect an extra bedroom and en-suite extension to cost around £61,500–£83,000 (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), or £2,200–£2,970 per m² including VAT. Professional fees for drawings and the structural engineer are listed separately on our prices page.

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 Emsworth

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 Emsworth 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. Start at your house

    We come to your home in Emsworth, measure up, check the ground floor walls and roof structure, and note anything near the boundaries.

  2. Drawings, then consent

    We draw the scheme, check it against the rules in England, and take it through the right consent with the council.

  3. Fixed price in writing

    With approved drawings and calculations, we give you a fixed build price and a programme you can plan around.

  4. 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 Emsworth

How much does an extra bedroom and en-suite extension cost in Emsworth?

Our guide for South East England, which covers Emsworth, is £2,200–£2,970 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 £61,500–£83,000 (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.

Which postcodes do you cover around Emsworth?

We cover Emsworth (PO10) and nearby places including Havant, South Hayling and Hayling Island, plus the rest of West Sussex. The first site visit is free.

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.

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.

Nearby

Other towns near Emsworth:

Other extensions in Emsworth

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

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