Spalding · Lincolnshire

Extra bedroom and en-suite extensions in Spalding

Thinking about an extra bedroom and en-suite extension in Spalding? We design it, take it through the approvals it needs and build it, with one team responsible from the first visit to the final certificate.

Useful details for planning an extra bedroom and en-suite extension in Spalding.

Postcode districts
PE11 and PE12
County / area
Lincolnshire, England
Price region
East Midlands
Guide price
£55,000–£74,000 (£1,960–£2,650 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
Bourne (9.8 miles), Market Deeping (10.3 miles), Boston (14.1 miles)
Distance to Lincoln
about 34.4 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%.

Spalding sits about 34.4 miles from Lincoln. Closer to home, Bourne is 9.8 miles away and Market Deeping 10.3 miles.

What it costs in Spalding

A guide price for Spalding: around £55,000–£74,000 (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). That works out at £1,960–£2,650 per m² of new floor space, including VAT at 20%. Design fees, structural calculations and approval fees are separate and listed on our prices page.

SpecPer m²A 4 m × 3.5 m footprint on two floors (28 m² of new floor space)
Essential£1,800–£2,430 per m²£50,500–£68,000
Standard£1,960–£2,650 per m²£55,000–£74,000
Premium£2,350–£3,180 per m²£66,000–£89,000

Planning and building regulations in Spalding

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 Spalding 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.

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.

How we'd run your project

  1. Free site visit

    We visit your home in Spalding, look at the structure, access and boundaries, and talk through what you want the new rooms to do.

  2. Design and approvals

    We draw the extension and check it against the rules for England, then apply for planning permission or a certificate of lawfulness, whichever fits.

  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 and sign-off

    Vetted teams working under S&K build the extension, and we arrange the building control completion certificate at the end.

Questions about extra bedroom and en-suite extensions in Spalding

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

Spalding 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.

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

Our guide for the East Midlands, which covers Spalding, is £1,960–£2,650 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 £55,000–£74,000 (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.

Who handles building regulations for a project in Spalding?

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.

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.

Nearby

Close to Spalding? We work across the area, including:

Other extensions in Spalding

All two-storey extension services in Spalding · Extra bedroom and en-suite extensions across Lincolnshire

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

CallGuide price