Double-storey extensions · Ballymena

Double-storey extensions in Ballymena

Double-storey extensions for homes in Ballymena and the surrounding parts of County Antrim, designed around your house and built by our teams under a single written contract.

Covering Ballymena

Alongside Ballymena, we also cover Magherafelt, Ballymoney (17 miles to the north-west) and Newtownabbey.

Homes in County Antrim

Across Northern Ireland you find city terraces, suburban semis and rural bungalows and farmhouses, so the right approach depends on the plot and the planning history.

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.

  • Measured survey, design and planning drawings
  • Structural engineer’s design and calculations
  • Windows, insulation, plastering, electrics and plumbing

What will a double-storey extension cost?

Use these ranges to budget for double-storey extensions; the survey turns them into a fixed price for the agreed specification.

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

Planning and building rules in Ballymena

Northern Ireland projects need planning clearance and building control approval from the local council. We prepare the applications and agree any work near neighbouring property directly with the neighbours.

Two-storey extensions in Northern Ireland normally need planning permission from the council, plus building control approval.

What can change the price or programme?

  • Neighbours’ light is assessed using the 45-degree guide many councils use.
  • The new roof is tied into the old one, so roof tiles and ridge details need to match.

What happens after I enquire?

  1. Start with a conversation. A short call or the online form is enough for us to understand what you want to build.
  2. We visit and measure. A surveyor checks the house, the boundaries and the ground, and discusses what is realistic.
  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.

Your questions answered

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.

How long does a two-storey extension take?

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

Can you visit a house in Ballymena 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 Ballymena.

Planning an extension, loft or new home?

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

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