Single-storey extensions · Northamptonshire

Single-storey extensions in Northamptonshire

We design and build single-storey extensions throughout Northamptonshire, with a fixed price in writing for the agreed specification and one point of contact.

Covering Northamptonshire

Our single-storey extensions service in Northamptonshire covers Northampton, Corby, Kettering and Wellingborough and more.

Homes in the East Midlands

Housing in the East Midlands includes Victorian terraces, inter-war semis and newer estates, with stone-built villages in some areas where conservation controls apply.

What does a single-storey extension involve?

A single-storey extension adds one level of new floor space to the back or side of a house, usually to open up a kitchen, dining or family room. It is the most common way to gain space without moving, and many can be built without a planning application.

  • Planning or lawful development certificate where needed
  • Brickwork, roof, glazing and insulation
  • First-fix and second-fix electrics, plastering and making good

How much should I budget for a single-storey extension?

Indicative costs for single-storey extensions. London and the South East usually sit towards the top of each range.

Single-storey extensionsGuide price incl. VAT
Standard specification£2,600 to £3,000 per m²
Good specification£3,000 to £3,500 per m²
High specification£3,500 to £4,000 per m²

Do you need permission for a single-storey extension in Northamptonshire?

In England we deal with the council’s planning team for permission or a lawful development certificate, with building control (the council or a registered building control approver) for inspections, and with neighbours under the Party Wall etc. Act 1996 where it applies.

In England a single-storey rear extension can often go ahead under permitted development: up to 3 m deep on an attached house or 4 m on a detached one, no higher than 4 m, with eaves no higher than 3 m within 2 m of a boundary.

What should I think about before starting?

  • Large glazed areas need to meet energy rules, which can shape the size of doors and rooflights.
  • Kitchens and doors have long lead times, so we order them early.

How does the project run?

  1. Send us the details. Give us a postcode, a rough idea of size and some photos, by phone, form or the guide price tool.
  2. Free site visit. We measure up, look at access, drains and the structure, and talk through options and budget.
  3. Design and fixed price. You get drawings and a written price for the agreed specification before anything is ordered.
  4. We build it. Work follows an agreed programme, with inspections at each stage and a final sign-off.

Your questions answered

How much does a single-storey extension cost?

Most single-storey extensions cost about £2,600 to £4,000 per square metre including VAT, depending on specification, glazing and ground conditions. We give a fixed price in writing for the agreed specification after the survey.

Do you need to dig up the drains?

Sometimes. If a public sewer runs under the extension, the water company has to agree a build-over or a diversion. We check this at survey stage.

Can you visit a house in Northamptonshire to quote?

Yes. After a short call we arrange a site visit to measure up and agree what the design needs to do, then send a written price.

Single-storey extensions near Northamptonshire

Learn more about single-storey extensions, or see every project we cover in Northamptonshire.

Planning an extension, loft or new home?

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