Newcastle · County Down

Two-storey side extensions in Newcastle

Our two-storey side extensions service in Newcastle covers everything: measured survey, design, planning or permitted development checks, structural design, building control and the build itself.

Quick reference for homeowners in Newcastle.

Postcode districts
BT31 and BT33
County / area
County Down, 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
Downpatrick (10.4 miles), Kilkeel (11.7 miles), Ballynahinch (12.7 miles)
Distance to Bangor (County Down)
about 31.9 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.

Newcastle sits about 31.9 miles from Bangor (County Down). Closer to home, Downpatrick is 10.4 miles away and Kilkeel 11.7 miles.

What it costs in Newcastle

A guide price for Newcastle: around £76,000–£101,500 for a 3 m × 7 m footprint on two floors (42 m² of new floor space). That works out at £1,800–£2,420 per m² of new floor space, including VAT at 20%. Keep a contingency of around 10% for things nobody can see until the ground is opened up.

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 Newcastle

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 Newcastle 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.

Matching the ridge and roof

A hipped house usually needs a hipped extension roof, and a gabled house a gable. Matching the pitch, tiles, ridge detail and brick bond is what makes a side extension look original rather than added, and councils look closely at it on a front-facing addition.

How we'd run your project

  1. Visit and first ideas

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

  2. Drawings, then consent

    We draw the scheme, check it against the rules in Northern Ireland, and take it through the right consent with the council.

  3. Technical design

    We prepare the building regulations drawings, structural calculations and specification so the build price can be fixed.

  4. Build and sign-off

    Vetted teams working under S&K build the extension, and we arrange the building control completion certificate at the end.

Questions about two-storey side extensions in Newcastle

Do I need planning permission for a two-storey side extension in Newcastle?

Newcastle is in Northern Ireland. Planning permission is needed: permitted development side extensions in Northern Ireland can't be more than 4 m high, which rules out two storeys.

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

Our guide for Northern Ireland, which covers Newcastle, 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.

Who handles building control for a project in Newcastle?

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.

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.

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

Close to Newcastle? We work across the area, including:

Other extensions in Newcastle

All two-storey extension services in Newcastle · Two-storey side extensions across County Down

Tell us about your house in Newcastle and we'll call you back to arrange a free, no-obligation visit.

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