In short: An HMO extension adds space to a shared house, usually a ground-floor bedroom with ensuite or a bigger communal kitchen. Across County Londonderry, the work is planned around Northern Ireland’s HMO rules and the standards the local council publishes.
- Nation
- Northern Ireland
- Pricing region
- Northern Ireland
- Postcode areas
- BT
- Main towns
- Londonderry County Borough, Derry, Coleraine
What do extensions for extra rooms in County Londonderry involve?
- Building control completion
- Foundations, structure and roof
- Planning route check and drawings
- Party wall coordination where needed
- Heating, insulation and glazing
- Fire separation and detection extended to the new space
Which rules apply in County Londonderry?
- 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.
- Doors on protected routes are typically FD30 or FD30S, self-closing on three hinges; emergency lighting is required in HMOs of 4 or more storeys.
- Kitchens, bathrooms and WCs must meet the 2019 living accommodation standard regulations and licence conditions.
In Northern Ireland, licensing is run centrally by the NI HMO Unit, and all new HMOs need planning permission and building control approval from the local council.
How much do extensions for extra rooms cost in County Londonderry?
| 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 |
Typical time on site: 8–14 weeks. For a figure for your house, try the guide-price tool.
Extensions for extra rooms by town in County Londonderry
Questions about extensions for extra rooms in County Londonderry
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 handle building control?
Yes, from application to completion certificate.
Do you carry out extensions for extra rooms across County Londonderry?
Yes, across the whole of County Londonderry, including Londonderry County Borough, Derry, Coleraine.
Who licenses HMOs in County Londonderry?
HMO licensing in County Londonderry, as everywhere in Northern Ireland, is run by the NI HMO Unit at Belfast City Council. Planning and building control are handled by the local council.
Other HMO services in County Londonderry
- Loft conversions for extra rooms in County Londonderry
- Communal kitchen refits in County Londonderry
- Layout changes and room reconfiguration in County Londonderry
- Large HMO conversions (7+ sharers) in County Londonderry
- Ensuite installation in County Londonderry
- House to HMO conversion in County Londonderry
- Small HMO conversions (3–6 sharers) in County Londonderry
- Full HMO refurbishment in County Londonderry