Double-storey extensions · Lancaster

Double-storey extensions in Lancaster

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

Covering Lancaster

We work in Lancaster (LA1) and the places around it, including Morecambe, Fleetwood and Thornton-Cleveleys.

Homes in the North West

Across the North West, Victorian terraces, inter-war semis and modern estates all feature, and brick or stone matching is chosen to suit each street.

What goes into 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.

  • Measured survey, design and planning drawings
  • Windows, insulation, plastering, electrics and plumbing
  • Joining the new first floor to the existing landing

What will a double-storey extension cost?

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

What approvals does a double-storey extension need in England?

Projects in England go through two separate checks. Planning (or confirmation that the work is permitted development) comes from the district, borough or unitary council, and building regulations approval comes from the council’s building control team or a registered building control approver. Where work touches a shared wall or digs near a neighbour’s foundations, the Party Wall etc. Act 1996 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 can change the price or programme?

  • 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. Design and fixed price. You get drawings and a written price for the agreed specification before anything is ordered.
  4. Build and hand over. Our teams build to the programme, building control inspects, and you get the completion paperwork at the end.

Questions about a double-storey extension in Lancaster

How long does a two-storey extension take?

Around 14 to 24 weeks on site, plus the planning period before that.

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.

Can you visit a house in Lancaster 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.

Also covering

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

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