An HMO extension adds space to a shared house, usually a ground-floor bedroom with ensuite or a bigger communal kitchen. In Antrim, a town of about 20,000 people, the work is planned around the HMO rules for Northern Ireland and the NI HMO standards and licence conditions.
- Area
- County Antrim, Northern Ireland
- Postcodes
- BT41
- Location
- 14 miles north-west of Belfast
- Pricing region
- Northern Ireland
What do extensions for extra rooms in Antrim involve?
- Heating, insulation and glazing
- Building control completion
- Fire separation and detection extended to the new space
- Kitchen or bedroom fit-out
- Ensuite drainage and extraction
Which rules apply in Antrim?
The rules below are the Northern Ireland-wide position for this kind of work. The NI HMO Unit’s standards and licence conditions apply on top, so we always check the address in Antrim before we price.
- All new HMOs need planning permission; councils such as Belfast apply HMO policy areas and limits on concentration.
- New HMOs need building control approval as well as planning permission.
- The NIFRS HMO Fire Safety Guide (July 2026) usually expects Grade D1 interlinked detection in smaller shared houses and a Grade A system with more than 6 occupants or over 200 m².
- Kitchens, bathrooms and WCs must meet the 2019 living accommodation standard regulations and licence conditions.
How much do extensions for extra rooms cost in Antrim?
| Item | UK typical | Local guide | Per |
|---|---|---|---|
| Single-storey extension, about 15 m² | £35,000 – £60,000 | £31,500 – £54,000 | project |
| Single-storey extension per m² | £1,800 – £4,000 | £1,600 – £3,600 | m² |
Use these as a starting point for budgeting. Access, condition and the council’s requirements in Antrim can move the figure either way, which is why we quote after seeing the house.
How long does it take?
Most jobs of this kind take 8–14 weeks. If a council deadline applies in Antrim, tell us at the first call so the programme is built around it.
When do Antrim landlords need it?
We usually get the call when:
- Adding a ground-floor room
- Moving to more sharers with consent
Questions about extensions for extra rooms in Antrim
Can I extend an HMO under permitted development?
Some extensions to houses are permitted development, but rules differ for HMOs and by nation and council. We check the address before design.
Do you cover all of Antrim?
Yes. We work across Antrim and the BT41 postcode areas, plus the rest of County Antrim. Nearby places we also cover include Ballymena, Newtownabbey, Belfast.
Does a shared house in Antrim need an HMO licence?
Yes, if 3 or more people forming more than two households live there as their main home and pay rent. Licensing for every council in Northern Ireland is run by the NI HMO Unit at Belfast City Council.
How much do extensions for extra rooms cost in Antrim?
Our guide ranges for Northern Ireland are in the table on this page, and the guide-price tool gives a figure for your house. A fixed written quote follows a free site visit.
Extensions for extra rooms near Antrim
- Ballymena · 10 mi
- Newtownabbey · 13 mi
- Belfast · 14 mi
- Lisburn · 15 mi
- Carrickfergus · 16 mi
- Holywood · 16 mi
- All of County Antrim
Other HMO services in Antrim
- Loft conversions for extra rooms in Antrim
- Communal kitchen refits in Antrim
- Layout changes and room reconfiguration in Antrim
- Large HMO conversions (7+ sharers) in Antrim
- Ensuite installation in Antrim
- House to HMO conversion in Antrim
- Void and between-tenancy refurbs in Antrim
- Escape routes, emergency lighting and fire stopping in Antrim