Sidmouth · Devon

Extra bedroom and en-suite extensions in Sidmouth

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

What we'd confirm first for a project in Sidmouth.

Postcode districts
EX10, EX11 and EX12
County / area
Devon, England
Price region
South West England
Guide price
£57,500–£78,000 (£2,060–£2,780 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
Honiton (7.8 miles), Exmouth (8.8 miles), Heavitree (11.4 miles)
Distance to Plymouth
about 45.4 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.

Sidmouth sits about 45.4 miles from Plymouth. Closer to home, Honiton is 7.8 miles away and Exmouth 8.8 miles.

What it costs in Sidmouth

Expect an extra bedroom and en-suite extension in Sidmouth to land somewhere around £57,500–£78,000 (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). Our South West England guide rate is £2,060–£2,780 per m², including VAT. 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£1,900–£2,560 per m²£53,000–£71,500
Standard£2,060–£2,780 per m²£57,500–£78,000
Premium£2,470–£3,340 per m²£69,000–£93,500

Planning and building regulations in Sidmouth

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 Sidmouth 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

  1. Start at your house

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

  2. Plans, then approval

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

  3. Price it properly

    Once the engineer's calculations are in, we fix the build price in writing, with a clear list of what's included.

  4. Build and hand over

    We manage the build from groundworks to decoration-ready finish and hand over with the completion paperwork.

Questions about extra bedroom and en-suite extensions in Sidmouth

Which postcodes do you cover around Sidmouth?

We cover Sidmouth (EX10, EX11 and EX12) and nearby places including Honiton, Exmouth and Heavitree, plus the rest of Devon. 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.

Who handles building regulations for a project in Sidmouth?

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.

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 Sidmouth

All two-storey extension services in Sidmouth · Extra bedroom and en-suite extensions across Devon

The quickest next step is a visit. We'll look at your house in Sidmouth and give you an honest view of the options.

CallGuide price