Carrickfergus · County Antrim

Extra bedroom and en-suite extensions in Carrickfergus

Thinking about an extra bedroom and en-suite extension in Carrickfergus? We design it, take it through the approvals it needs and build it, with one team responsible from the first visit to the final certificate.

Quick reference for homeowners in Carrickfergus.

Postcode districts
BT38
County / area
County Antrim, Northern Ireland
Price region
Northern Ireland
Guide price
£49,500–£66,500 (£1,760–£2,380 per m²), plus £5,500–£11,000 for the en-suite
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
Greenisland (2.9 miles), Jordanstown (4.4 miles), Holywood (5.4 miles)
Distance to Belfast
about 9.5 miles
First visit
Free, no obligation

About an extra bedroom and en-suite extension

This service suits you if you need another bedroom, or want a main bedroom with its own bathroom, without converting the loft or moving. You get a first-floor layout that connects well to your landing, an en-suite designed for plumbing and ventilation, a useful room downstairs, the approvals your nation needs and the build, managed by us and carried out by vetted teams working under S&K.

Around Carrickfergus we also work in Greenisland, Jordanstown and Holywood, and across the rest of County Antrim. Postcode district in and near Carrickfergus: BT38.

What it costs in Carrickfergus

Using our Northern Ireland rates, an extra bedroom and en-suite extension with a 4 m × 3.5 m footprint on two floors (28 m² of new floor space) comes to about £49,500–£66,500 (plus £5,500–£11,000 for the en-suite), including VAT. Bigger or more glazed designs cost more per m². These are guides, not quotes. Ground conditions, steelwork and access can move the figure either way.

SpecPer m²A 4 m × 3.5 m footprint on two floors (28 m² of new floor space)
Essential£1,620–£2,190 per m²£45,500–£61,000
Standard£1,760–£2,380 per m²£49,500–£66,500
Premium£2,110–£2,850 per m²£59,000–£80,000

Planning and building control in Carrickfergus

In Northern Ireland, a rear extra bedroom extension can be permitted development within 3 m of the original rear wall and 7 m from the rear boundary. Upper side windows within 15 m of a neighbouring boundary must be obscure-glazed and non-opening. Other designs need a planning application costing £347, plus building control approval.

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 Carrickfergus homes

Sound and privacy

Bedrooms above a kitchen or family room benefit from an insulated floor to reduce noise. Side-facing upstairs windows usually have to be obscure-glazed, so we place the main bedroom window to the rear and the en-suite window to the side where possible.

Escape window and fire safety

A new first-floor bedroom needs an escape window with a clear opening of at least 0.33 m², at least 450 mm wide and high, and the bottom no more than 1,100 mm above the floor, unless there is a protected route to the stairs. We design the windows to meet this.

How we'd run your project

  1. Measure and listen

    A visit to Carrickfergus 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. 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 sign-off

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

Questions about extra bedroom and en-suite extensions in Carrickfergus

Who handles building control for a project in Carrickfergus?

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 an extra bedroom and en-suite extension in Carrickfergus?

Carrickfergus 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 long does an extra bedroom and en-suite 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.

How big should a new double bedroom be?

There is no legal minimum size for a bedroom in a house you own, so the test is whether it works. A comfortable double needs room for the bed with space to walk round it, wardrobes and a door that opens freely. We draw furniture on the plans so you can judge the space before anything is built.

What goes on the ground floor below a new bedroom?

Whatever suits you: a bigger kitchen, a family room, a study, a utility or a downstairs shower room. The ground floor usually costs about the same whatever it is used for, apart from kitchen units and bathroom fittings, which are priced separately.

Nearby

We also cover places near Carrickfergus, including:

Other extensions in Carrickfergus

All two-storey extension services in Carrickfergus · Extra bedroom and en-suite extensions across County Antrim

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

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