Covering Belfast
Alongside Belfast, we also cover Newtownabbey (4 miles to the north), Holywood and Lisburn.
Homes in County Antrim
Housing in Northern Ireland mixes terraces in Belfast and Derry with detached houses and bungalows in towns and rural areas, many with room to extend.
What does a basement conversion involve?
A basement conversion turns an existing cellar into dry, usable rooms, or excavates a new basement under a house. Converting an existing cellar is far simpler and cheaper than digging a new one, and often does not need planning permission.
- Damp and structural survey
- Underpinning or lowering the floor where needed
- Ventilation, heating and electrics
How much should I budget for a basement conversion?
What basement and cellar conversions typically cost. These are guide ranges; the written quote for your house replaces them.
| Basement and cellar conversions | Guide price incl. VAT |
|---|---|
| Existing cellar conversion | £1,900 to £3,000 per m² |
| New basement excavation | £4,200 to £6,600 per m² |
What approvals does a basement conversion need in Northern Ireland?
In Northern Ireland the council handles both planning and building control. Permitted development rules are set by the Planning (General Permitted Development) Order (Northern Ireland) 2015, and there is no party wall act, so we agree access and protection with neighbours in writing.
In Northern Ireland new basements and external changes normally need planning permission; building control approval is needed.
What should Belfast homeowners check first?
- A pump for the drainage system needs a battery back-up.
- Headroom of about 2.1 m or more is needed, which may mean lowering the floor.
How does the project run?
- Send us the details. Give us a postcode, a rough idea of size and some photos, by phone, form or the guide price tool.
- Survey at your house. We look at the existing structure, services and access, and agree what the design needs to achieve.
- Price and paperwork. The design is priced line by line, and we submit the planning and building control applications.
- Construction and completion. One site lead co-ordinates every trade through to the building control certificate.
Basement and cellar conversions: common questions
How do you keep a basement dry?
With a designed waterproofing system, usually a cavity drain membrane draining to a pump, sometimes combined with tanking.
How long does it take?
About 6 to 12 weeks for a cellar conversion and 16 to 30 weeks for a new basement.
Can you visit a house in Belfast to quote?
Yes. After a short call we arrange a site visit to measure up and agree what the design needs to do, then send a written price.
Other towns nearby
- Basement and cellar conversions in Newtownabbey
- Basement and cellar conversions in Holywood
- Basement and cellar conversions in Lisburn
- Basement and cellar conversions in Comber
Learn more about basement and cellar conversions, or see every project we cover in Belfast.