Double-storey extensions · Havant

Double-storey extensions in Havant

From the first site visit to the final building control sign-off, we manage double-storey extensions in Havant so you only have one company to deal with.

Covering Havant

Alongside Havant, we also cover Waterlooville, Portsmouth (6 miles to the south-west) and Gosport.

Homes in the South East

The South East has a lot of 1930s and post-war semi-detached housing, well suited to rear extensions and hip-to-gable loft conversions, alongside period properties in conservation areas that need a more careful design.

What is a double-storey extension?

A double-storey extension adds new rooms on both the ground and first floor in one build, typically a larger kitchen or living space downstairs and an extra bedroom or bathroom above. Because the roof and foundations are shared, the cost per square metre is usually lower than a single-storey extension.

  • Foundations, steelwork, brick and block walls, roof
  • Windows, insulation, plastering, electrics and plumbing
  • Joining the new first floor to the existing landing

How much does a double-storey extension cost in Havant?

Typical ranges for double-storey extensions. Ground conditions, access and specification move the final figure, which we fix in writing before work starts.

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 Havant?

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.

What can change the price or programme?

  • Side extensions close to a boundary are often set back or stepped down so they do not create a terraced effect.
  • Neighbours’ light is assessed using the 45-degree guide many councils use.

From first call to completion

  1. Tell us about the project. Call, use the guide price tool or send the form with a few photos and a postcode.
  2. We visit and measure. A surveyor checks the house, the boundaries and the ground, and discusses what is realistic.
  3. Drawings, approvals, written quote. We prepare the design, apply for the approvals it needs, and give you a fixed price in writing.
  4. We build it. Work follows an agreed programme, with inspections at each stage and a final sign-off.

What people ask before starting

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.

Is a two-storey extension better value than a single-storey one?

Per square metre, usually yes, because the foundations and roof serve two floors of space.

Can you visit a house in Havant 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.

Double-storey extensions in nearby towns

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

Planning an extension, loft or new home?

Get a guide price in two minutes, then book a free site visit.

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