Camborne · Cornwall

Extra bedroom and en-suite extensions in Camborne

Homes in Camborne with a bit of space to the side or rear can often take an extra bedroom and en-suite extension. We'll tell you honestly whether yours can, and what approvals it needs.

Before you start in Camborne, here's what applies.

Postcode districts
TR14 and TR27
County / area
Cornwall, 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
Redruth (3.5 miles), Helston (7.7 miles), Falmouth (10.8 miles)
Distance to Truro
about 11.3 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 postcode districts TR14 and TR27 in and around Camborne, along with neighbouring Redruth, Helston and Falmouth.

What it costs in Camborne

Using our South West England rates, an extra bedroom and en-suite extension with a 4 m × 3.5 m footprint on two floors (28 m² of new floor space) comes to about £57,500–£78,000 (plus £5,500–£11,000 for the en-suite), including VAT. Bigger or more glazed designs cost more per m². These are guides, not quotes. Ground conditions, steelwork and access can move the figure either way.

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 Camborne

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 Camborne 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.

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. Understand the brief

    At your home in Camborne we agree what you need: bedroom count, bathroom, kitchen space, and how much garden you want to keep.

  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. Technical design

    We prepare the building regulations drawings, structural calculations and specification so the build price can be fixed.

  4. On site

    One project lead runs the job, keeps you updated and arranges inspections at each stage until completion.

Questions about extra bedroom and en-suite extensions in Camborne

Which postcodes do you cover around Camborne?

We cover Camborne (TR14 and TR27) and nearby places including Redruth, Helston and Falmouth, plus the rest of Cornwall. The first site visit is free.

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

Our guide for South West England, which covers Camborne, is £2,060–£2,780 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 £57,500–£78,000 (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.

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

The same service in neighbouring towns:

Other extensions in Camborne

All two-storey extension services in Camborne · Extra bedroom and en-suite extensions across Cornwall

Ready to talk it through? Call us or send the form and we'll arrange a visit to your home in Camborne.

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