Chatteris · Cambridgeshire

Two-storey rear extensions in Chatteris

Adding a two-storey rear extension in Chatteris gives you two new rooms stacked on one footprint. Here's how we'd approach it, what it typically costs and the rules that apply in England.

Useful details for planning a two-storey rear extension in Chatteris.

Postcode districts
PE16 and PE26
County / area
Cambridgeshire, England
Price region
East of England
Guide price
£57,500–£78,000 (£2,060–£2,780 per m²)
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
March (6.7 miles), Ely (9.7 miles), St Ives (10.1 miles)
Distance to Peterborough
about 15 miles
First visit
Free, no obligation

About a two-storey rear extension

A two-storey rear extension is a new two-floor addition built onto the back of your house, usually giving a larger kitchen or living space on the ground floor and one or two bedrooms or a bathroom above. Because both floors share one set of foundations and one roof, it adds a lot of floor space for the garden it uses. In some cases it can be built under permitted development, depending on where you live.

Chatteris sits about 15.0 miles from Peterborough. Closer to home, March is 6.7 miles away and Ely 9.7 miles.

What it costs in Chatteris

Most of the cost of a two-storey rear extension is set by its size and specification. For Chatteris 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 for a 4 m × 3.5 m footprint on two floors (28 m² of new floor space). 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 Chatteris

In England, a two-storey rear extension can be permitted development if it goes no more than 3 m beyond the rear wall of the original house, stays at least 7 m from the rear boundary and matches the house's materials and roof pitch. It is not permitted development in conservation areas, National Landscapes, National Parks, World Heritage Sites or the Broads. Otherwise a householder application costs £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 Chatteris homes

Depth and neighbours' light

Councils check that a two-storey rear extension does not take too much light or outlook from neighbouring windows, and many use a 45-degree line drawn from the nearest habitable window. We test this at sketch stage, so the depth you are shown is one that can realistically be approved.

Opening up the ground floor

Knocking through the old rear wall means steel beams to carry the first floor and roof above. The structural engineer sets the beam sizes, padstones and any posts, and we plan them early so the open-plan layout you want is the one that gets built.

How we'd run your project

  1. Understand the brief

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

  2. Choose the approval route

    Some designs fit permitted development, most need a householder application. We decide which applies in England before drawing in detail.

  3. Detail and price

    Construction drawings, engineer's calculations and building control sign-off, then a written fixed price for the build.

  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 two-storey rear extensions in Chatteris

Who handles building regulations for a project in Chatteris?

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.

Which postcodes do you cover around Chatteris?

We cover Chatteris (PE16 and PE26) and nearby places including March, Ely and St Ives, plus the rest of Cambridgeshire. The first site visit is free.

How long does a two-storey rear 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.

Will a two-storey rear extension block my neighbour's light?

It can if it is too deep or too close to the boundary, which is why councils look closely at its effect on neighbouring windows and gardens. We test the design against light and outlook early, keep the first floor shorter or set in where needed, and use a hipped roof to reduce bulk on the boundary side.

Can I have a balcony on a two-storey rear extension?

In England, balconies, verandas and raised platforms are not permitted development, so a balcony on a two-storey rear extension needs planning permission. A Juliet balcony, a guard rail across full-height doors with no platform to stand on, is often a practical alternative, but it still needs checking against the rules and the council's approach to overlooking.

Nearby

We also cover places near Chatteris, including:

Other extensions in Chatteris

All two-storey extension services in Chatteris · Two-storey rear extensions across Cambridgeshire

Send us your postcode and a few details. We'll get back to you to arrange a visit and talk through your options.

CallGuide price