Castlederg · County Tyrone

Two-storey side extensions in Castlederg

A two-storey side extension is one of the most space-efficient ways to add bedrooms and living space to a house in Castlederg, because the new floors share one set of foundations and one roof.

The basics for Castlederg at a glance.

Postcode districts
BT81
County / area
County Tyrone, 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
Sion Mills (7.4 miles), Strabane (9.5 miles), Omagh (13.9 miles)
Distance to Omagh
about 13.9 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.

Around Castlederg we also work in Sion Mills, Strabane and Omagh, and across the rest of County Tyrone. Postcode district in and near Castlederg: BT81.

What it costs in Castlederg

Most of the cost of a two-storey side extension is set by its size and specification. For Castlederg and the rest of Northern Ireland, our guide is £1,800–£2,420 per m² including VAT, so about £76,000–£101,500 for a 3 m × 7 m footprint on two floors (42 m² of new floor space). Design fees, structural calculations and approval fees are separate and listed on our prices page.

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 Castlederg

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 Castlederg homes

Set-down and set-back

Councils usually want a two-storey side extension to look subordinate to the house. Setting the front wall back from the main front and dropping the ridge slightly below the main roof helps it read as an addition, and is often expected in local design guidance.

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. Measure and listen

    A visit to Castlederg to understand how you live in the house now and what the extra rooms need to do, plus a first look at the structure.

  2. Drawings and permission

    Our designers produce plans and elevations, then we take care of planning or permitted development checks with the council covering Castlederg.

  3. Price it properly

    Once the engineer's calculations are in, we fix the build price in writing, with a clear list of what's included.

  4. On site

    One project lead runs the job, keeps you updated and arranges inspections at each stage until completion.

Questions about two-storey side extensions in Castlederg

Who handles building control for a project in Castlederg?

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.

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

Castlederg 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 Castlederg?

Our guide for Northern Ireland, which covers Castlederg, 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.

Which postcodes do you cover around Castlederg?

We cover Castlederg (BT81) and nearby places including Sion Mills, Strabane and Omagh, plus the rest of County Tyrone. The first site visit is free.

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

We also cover places near Castlederg, including:

Other extensions in Castlederg

All two-storey extension services in Castlederg · Two-storey side extensions across County Tyrone

Ready to talk it through? Call us or send the form and we'll arrange a visit to your home in Castlederg.

CallGuide price