Part single, part two-storey extensions in Castlederg

Before you start in Castlederg, here's what applies.

Postcode districts: BT81
County / area: County Tyrone, Northern Ireland
Price region: Northern Ireland
Guide price: £63,500–£87,000 (£1,760–£2,420 per m²)
Approval route: It may be permitted development if it goes no more than 3 m beyond the original rear wall and stays 7 m from the rear boundary.
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 part single, part two-storey extension

A part single, part two-storey extension is an extension where the ground floor is wider or deeper than the floor above, so only part of it rises to two storeys. It usually gives a large kitchen or living area with roof lights below and one bedroom or bathroom above. It is often a good way to add space while limiting the effect on neighbours.

We cover Castlederg (BT81) and the places around it, including Sion Mills (7.4 miles), Strabane (9.5 miles) and Omagh.

What it costs in Castlederg

For budgeting in Castlederg, allow around £63,500–£87,000 for a part single, part two-storey extension with a 6 m × 4 m ground floor and a first floor over half of it (36 m² in total). That's based on £1,760–£2,420 per m² including VAT for Northern Ireland. Kitchens, bathroom fittings and flooring are priced separately so you can compare like with like.

Spec	Per m²	A 6 m × 4 m ground floor and a first floor over half of it (36 m² in total)
Essential	£1,620–£2,230 per m²	£58,500–£80,000
Standard	£1,760–£2,420 per m²	£63,500–£87,000
Premium	£2,110–£2,900 per m²	£76,000–£104,500

Planning and building control in Castlederg

In Northern Ireland, the extension can be permitted development if it goes no more than 3 m beyond the original rear wall and stays at least 7 m from the rear boundary, with height, materials and roof pitch conditions met. Specified protected areas are excluded. If the design goes further, a planning application costs £347 per dwelling, and building control approval is needed either way.

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

The roof junction

Where the single-storey roof meets the two-storey wall you need a sound weathering detail, usually a lead or similar flashing, and enough height for roof lights or a lantern. We set the roof falls and the upstairs window sill heights together so they do not clash.

Structure at the step

The first-floor wall above often sits over the new open-plan space, so it needs a steel beam or frame to carry it. Loads come down at different points than in a full two-storey design, and the engineer sizes the foundations to suit each part.

How we'd run your project

Understand the brief
At your home in Castlederg we agree what you need: bedroom count, bathroom, kitchen space, and how much garden you want to keep.
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.
Technical design
We prepare the building regulations drawings, structural calculations and specification so the build price can be fixed.
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 part single, part two-storey 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 part single, part two-storey extension in Castlederg?

Castlederg is in Northern Ireland. It may be permitted development if it goes no more than 3 m beyond the original rear wall and stays 7 m from the rear boundary.

How much does a part single, part two-storey extension cost in Castlederg?

Our guide for Northern Ireland, which covers Castlederg, is £1,760–£2,420 per m² including VAT. A typical project with a 6 m × 4 m ground floor and a first floor over half of it (36 m² in total) comes to about £63,500–£87,000. Design and approval fees are extra, and we fix the build price in writing once the design is agreed.

Which side should the two-storey part go on?

Usually the side furthest from the nearest neighbour's windows, so the single-storey part sits nearest them and keeps their light. Other factors are where the stairs land upstairs, which room needs the extra space and where drains run. We sketch options at the design stage and explain which is most likely to be approved.

Can the single-storey part be deeper than the two-storey part?

With planning permission, yes, and that is often the point of the design: the ground floor projects further into the garden while the first floor stays back from neighbours. Under permitted development, the depth limits for extensions of more than one storey can apply to the whole extension, so we confirm which route applies before drawings are finalised.

Nearby

Other towns near Castlederg:

Other extensions in Castlederg

All two-storey extension services in Castlederg · Part single, part two-storey extensions across County Tyrone

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