Double-storey extensions · Washington

Double-storey extensions in Washington

Homeowners in Washington can get double-storey extensions from one company: the design, the paperwork and the building work sit with us rather than with three separate firms.

Covering Washington

Our coverage around Washington (NE37, NE38) also includes Chester-le-Street, Felling and Houghton-le-Spring.

Homes in the North East

Housing across the North East ranges from colliery terraces and Tyneside flats to suburban semis and modern estates, each with different options for extending.

What is a double-storey extension?

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.

  • 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 Washington?

Guide prices for double-storey extensions, including VAT where it applies. Your fixed price is confirmed in writing after the survey.

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

How is a double-storey extension approved in Washington?

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?

  • 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. Start with a conversation. A short call or the online form is enough for us to understand what you want to build.
  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.

Questions about a double-storey extension in Washington

Does a two-storey extension need planning permission?

Usually yes. In England some two-storey rear extensions are permitted development, but side extensions over one storey always need planning permission.

How long does a two-storey extension take?

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

Who deals with the council for a project in Washington?

We do. We prepare the drawings, submit planning or permitted development paperwork if needed, and arrange building control inspections.

Double-storey extensions in nearby towns

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

Planning an extension, loft or new home?

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