Two-storey wraparound extensions in Kettering

The basics for Kettering at a glance.

Postcode districts: NN14, NN15 and NN16
County / area: Northamptonshire, England
Price region: East Midlands
Guide price: £118,000–£162,000 (£2,110–£2,890 per m²)
Approval route: Planning permission is needed: the side part takes it outside permitted development in England.
Nearest towns: Desborough (5 miles), Wellingborough (6.7 miles), Corby (6.9 miles)
Distance to Northampton: about 12.2 miles
First visit: Free, no obligation

About a two-storey wraparound extension

A two-storey wraparound extension is an L-shaped addition that extends both the side and the rear of your house, on two floors. It gives one of the largest gains in floor space of any extension, typically a big open-plan kitchen and living area below and two or more bedrooms or bathrooms above. In England it needs planning permission, because the side part is more than one storey.

Around Kettering we also work in Desborough, Wellingborough and Corby, and across the rest of Northamptonshire. Postcode districts in and near Kettering: NN14, NN15 and NN16.

What it costs in Kettering

For budgeting in Kettering, allow around £118,000–£162,000 for a two-storey wraparound extension with an L-shaped footprint of about 28 m² wrapping the side and rear, on two floors (56 m² of new floor space). That's based on £2,110–£2,890 per m² including VAT for the East Midlands. Keep a contingency of around 10% for things nobody can see until the ground is opened up.

Spec	Per m²	An L-shaped footprint of about 28 m² wrapping the side and rear, on two floors (56 m² of new floor space)
Essential	£1,940–£2,660 per m²	£108,500–£149,000
Standard	£2,110–£2,890 per m²	£118,000–£162,000
Premium	£2,530–£3,470 per m²	£141,500–£194,500

Planning and building regulations in Kettering

In England, a two-storey wraparound extension needs householder planning permission, because any extension beyond a side wall must be single storey to be permitted development. The application costs £548 (or £575 for applications made from 8 December 2026). Councils weigh the side part against the street scene and the rear part against neighbours' light and outlook, and should decide within 8 weeks of validation.

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 Kettering homes

The corner post

At the outside corner of the L, there is no existing wall to carry the floor above. Opening the ground floor fully usually means a steel frame or a corner post, and the engineer's design sets how slim it can be. We decide early whether you want a clear corner or a visible post.

Phasing the build

A wraparound touches two sides of the house at once, so the kitchen and often the rear rooms are out of use for part of the build. We plan the sequence so you keep a working kitchen and bathroom for as long as possible, or advise when moving out briefly makes sense.

How we'd run your project

Free site visit
We visit your home in Kettering, look at the structure, access and boundaries, and talk through what you want the new rooms to do.
Drawings and permission
Our designers produce plans and elevations, then we take care of planning or permitted development checks with the council covering Kettering.
Structure and building control
A structural engineer sizes the foundations and steels, and we get building regulations approval before work starts.
On site
One project lead runs the job, keeps you updated and arranges inspections at each stage until completion.

Questions about two-storey wraparound extensions in Kettering

Do I need planning permission for a two-storey wraparound extension in Kettering?

Kettering is in England, so England planning rules apply. Planning permission is needed: the side part takes it outside permitted development in England. If in doubt, a lawful development certificate or a planning application gives you certainty before you build.

How long does a two-storey wraparound 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.

How much does a two-storey wraparound extension cost in Kettering?

Our guide for the East Midlands, which covers Kettering, is £2,110–£2,890 per m² including VAT. A typical project with an L-shaped footprint of about 28 m² wrapping the side and rear, on two floors (56 m² of new floor space) comes to about £118,000–£162,000. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.

How much floor space does a wraparound extension add?

It depends on the width of the side plot and the depth at the rear. Our guide prices are based on a typical wraparound with an L-shaped footprint of about 28 m² wrapping the side and rear, on two floors (56 m² of new floor space). Yours may be larger or smaller, and the measured survey shows what your plot can take.

Does a wraparound extension need steel?

Almost always. Opening the corner of the house and the old rear wall to make one open-plan space means steel beams, and often a steel post or frame at the outside corner. The structural engineer sizes these, and the steel is ordered once the design is fixed, which is one reason a wraparound needs careful sequencing.

Nearby

Nearby towns we cover for two-storey wraparound extensions:

Other extensions in Kettering

All two-storey extension services in Kettering · Two-storey wraparound extensions across Northamptonshire

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