Ballymoney · County Antrim

Two-storey side extensions in Ballymoney

We plan and build two-storey side extensions for homeowners in Ballymoney and nearby. Every project starts with a free visit and a design stage priced in writing before any work begins.

The basics for Ballymoney at a glance.

Postcode districts
BT53
County / area
County Antrim, Northern Ireland
Price region
Northern Ireland
Guide price
£76,000–£101,500 (£1,800–£2,420 per m²)
Approval route
Planning permission is needed: permitted development side extensions in Northern Ireland can't be more than 4 m high, which rules out two storeys.
Nearest towns
Coleraine (7.5 miles), Portrush (10.2 miles), Portstewart (11.1 miles)
Distance to Belfast
about 40.2 miles
First visit
Free, no obligation

About a two-storey side extension

A two-storey side extension is a new two-floor addition built into the space beside your house, often over a driveway or side passage. It typically adds one or two bedrooms upstairs and a utility, study or larger kitchen below, without giving up rear garden.

Around Ballymoney we also work in Coleraine, Portrush and Portstewart, and across the rest of County Antrim. Postcode district in and near Ballymoney: BT53.

What it costs in Ballymoney

Expect a two-storey side extension in Ballymoney to land somewhere around £76,000–£101,500 for a 3 m × 7 m footprint on two floors (42 m² of new floor space). Our Northern Ireland guide rate is £1,800–£2,420 per m², including VAT. The fastest way to a firmer number is a free site visit, after which we price the design stage in writing.

SpecPer m²A 3 m × 7 m footprint on two floors (42 m² of new floor space)
Essential£1,660–£2,230 per m²£69,500–£93,500
Standard£1,800–£2,420 per m²£76,000–£101,500
Premium£2,160–£2,900 per m²£91,000–£122,000

Planning and building control in Ballymoney

In Northern Ireland, permitted development for two-storey work is set out for rear extensions, so a two-storey side extension normally needs a planning application. The fee is £347 per dwelling, and councils aim for an average of 15 weeks on local applications. You also need building control approval from the council under the Technical Booklets.

Approval in Northern Ireland: Planning application for works to a house: £347. Councils aim to decide local applications within an average of 15 weeks; many take longer.

Building control: Building control approval from the local council under the Building Regulations (Northern Ireland), using the Technical Booklets.

Design points for Ballymoney homes

Side windows, boundaries and gutters

Upstairs windows in the side wall face the neighbour, so they are usually obscure-glazed and fixed, or left out. Building close to the boundary also raises questions about foundations, overhanging gutters and access for maintenance, so we design the eaves and gutter to stay within your land.

Avoiding a terracing effect

Where semi-detached houses sit close together, side extensions on neighbouring houses can join up and turn a row of pairs into a terrace. Many councils ask for a gap to the boundary at first floor to stop this, so we check local guidance before fixing the width.

How we'd run your project

  1. Visit and first ideas

    One of our team visits your house in Ballymoney, checks the walls, roof and drains, and sketches out options with you.

  2. Choose the approval route

    Some designs fit permitted development, most need a householder application. We decide which applies in Northern Ireland before drawing in detail.

  3. Fixed price in writing

    With approved drawings and calculations, we give you a fixed build price and a programme you can plan around.

  4. Build and hand over

    We manage the build from groundworks to decoration-ready finish and hand over with the completion paperwork.

Questions about two-storey side extensions in Ballymoney

How long does a two-storey side extension take?

Allow 4 to 8 weeks for survey and design, then the approval period (councils aim to decide local applications within an average of 15 weeks; many take longer), then 4 to 8 weeks of technical design, which can overlap. The build itself usually takes 14 to 20 weeks, longer for large or complex designs.

Who handles building control for a project in Ballymoney?

We handle it as part of the project. What's needed in Northern Ireland: building control approval from the local council under the Building Regulations (Northern Ireland), using the Technical Booklets. We prepare the drawings and the engineer's calculations, book the inspections and pass you the completion paperwork at the end.

Which postcodes do you cover around Ballymoney?

We cover Ballymoney (BT53) and nearby places including Coleraine, Portrush and Portstewart, plus the rest of County Antrim. The first site visit is free.

How much does a two-storey side extension cost in Ballymoney?

Our guide for Northern Ireland, which covers Ballymoney, is £1,800–£2,420 per m² including VAT. A typical project with a 3 m × 7 m footprint on two floors (42 m² of new floor space) comes to about £76,000–£101,500. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.

Can I build a two-storey side extension over my driveway?

Yes, if the drive is wide enough for a useful room and the council accepts the design. You may lose off-road parking, which some councils weigh up, and the foundations need to suit the ground below. We check parking, drains and meter positions at the free site visit before any drawings are prepared.

Nearby

Nearby towns we cover for two-storey side extensions:

Other extensions in Ballymoney

All two-storey extension services in Ballymoney · Two-storey side extensions across County Antrim

Book a free site visit in Ballymoney and we'll tell you what's possible, what approvals you need and what the design stage would cost.

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