Double-storey extensions · Grantham

Double-storey extensions in Grantham

We take on double-storey extensions in Grantham as a complete project: survey, drawings, planning or permitted development checks, building control and the construction itself.

Covering Grantham

Grantham sits 22 miles south of Lincoln, with Newark-on-Trent 13 miles to the north-west and Melton Mowbray 14 miles to the south-west.

Homes in the East Midlands

Across the East Midlands you find everything from city terraces to modern estates and stone villages, so the right extension depends a lot on the street and the materials around it.

What is included in a double-storey extension in Grantham?

Two-storey work has to sit comfortably with the house and the neighbours, so most of the design effort goes into the roofline, window positions and how the new first floor connects to the landing. We handle the planning application, the structural design and the building control process, then build, roof and finish both floors.

  • Householder planning application
  • Structural engineer’s design and calculations
  • Foundations, steelwork, brick and block walls, roof

What is the guide price for a double-storey extension in Grantham?

What double-storey extensions typically cost. These are guide ranges; the written quote for your house replaces them.

Double-storey extensionsGuide price incl. VAT
Standard specification£2,400 to £2,900 per m²
Good specification£2,900 to £3,400 per m²
High specification£3,400 to £3,850 per m²

Do you need permission for a double-storey extension in Grantham?

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.

Two-storey rear extensions can sometimes be permitted development in England (no more than 3 m deep, at least 7 m from the rear boundary, roof pitch to match), but most two-storey and all two-storey side extensions need householder planning permission. Expect around eight weeks for a decision once the application is validated.

What should Grantham homeowners check first?

  • The new roof is tied into the old one, so roof tiles and ridge details need to match.
  • The first-floor link can mean moving a bathroom or reshaping the landing.

What happens after I enquire?

  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. Survey at your house. We look at the existing structure, services and access, and agree what the design needs to achieve.
  3. Price and paperwork. The design is priced line by line, and we submit the planning and building control applications.
  4. Build and hand over. Our teams build to the programme, building control inspects, and you get the completion paperwork at the end.

Double-storey extensions: common questions

How much does a two-storey extension cost?

Typically about £2,400 to £3,850 per square metre of new floor area including VAT. A 40 m² extension across two floors is often around £100,000 to £150,000 depending on specification.

Will we need to move out?

Most people stay. The noisiest stage is when we break through into the existing first floor, which we plan for a short window.

Do you work in Grantham?

Yes. Grantham is within our coverage for double-storey extensions, along with nearby Newark-on-Trent and Melton Mowbray.

Also covering

Learn more about double-storey extensions, or see every project we cover in Grantham.

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