Extra bedroom and en-suite extensions in Frinton-on-Sea

Useful details for planning an extra bedroom and en-suite extension in Frinton-on-Sea.

Postcode districts: CO13
County / area: Essex, England
Price region: East of 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: Walton-on-the-Naze (1.6 miles), Clacton-on-Sea (4.7 miles), Harwich (7.9 miles)
Distance to Southend-on-Sea: about 30.4 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.

Around Frinton-on-Sea we also work in Walton-on-the-Naze, Clacton-on-Sea and Harwich, and across the rest of Essex. Postcode district in and near Frinton-on-Sea: CO13.

What it costs in Frinton-on-Sea

Most of the cost of an extra bedroom and en-suite extension is set by its size and specification. For Frinton-on-Sea and the rest of the East of England, our guide is £2,060–£2,780 per m² including VAT, so about £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). The fastest way to a firmer number is a free site visit, after which we price the design stage in writing.

Spec	Per m²	A 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 Frinton-on-Sea

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 Frinton-on-Sea 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

Free site visit
We visit your home in Frinton-on-Sea, look at the structure, access and boundaries, and talk through what you want the new rooms to do.
Get it approved
Once you're happy with the design we submit it to the council for Frinton-on-Sea and deal with any questions from the planning officer.
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.
Finish and certify
Second fix, plastering and making good, then building control's final inspection and the completion paperwork.

Questions about extra bedroom and en-suite extensions in Frinton-on-Sea

Which postcodes do you cover around Frinton-on-Sea?

We cover Frinton-on-Sea (CO13) and nearby places including Walton-on-the-Naze, Clacton-on-Sea and Harwich, plus the rest of Essex. The first site visit is free.

Who handles building regulations for a project in Frinton-on-Sea?

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 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.

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 Frinton-on-Sea

All two-storey extension services in Frinton-on-Sea · Extra bedroom and en-suite extensions across Essex

Want a figure first? Try our guide price tool, then book a free visit to firm it up.