Extensions cost in Belfast
2026 prices for County Antrim · Northern Ireland
Extensions in Belfast typically costs between £25,500 and £102,000, with most homeowners landing near £63,750. Local pricing sits about 15% below the UK average. The lowest labour and materials costs in the UK, with its own building control and planning system.
£25,500 – £102,000
UK average £2,200 per m² · Belfast index 85
Free · Up to 3 local quotes · No obligation
Extensions prices in Belfast by finish level
| FINISH LEVEL | BELFAST COST | WHAT'S INCLUDED |
|---|---|---|
| Budget | £25,500 – £38,500 | Entry-level materials, existing layout retained |
| Mid-range | £37,000 – £55,500 | Better fittings, some layout change |
| Premium | £49,500 – £74,500 | High-specification materials and full redesign |
£35,063
About 55% of a typical Belfast job, at Northern Ireland day rates.
£28,687
Materials pricing is broadly national — this is where specification, not location, drives your total.
What affects extensions cost in Belfast
Red-brick Victorian terraces across the inner city with 1970s estates beyond. Northern Ireland operates its own building control and planning system, and costs are the lowest in the UK.
- Drainage runs needing diversion
- Party wall agreements with neighbours
- Poor ground conditions requiring deeper foundations
Rules in Belfast
Building control and planning applications for extensions work in Belfast go through Belfast City Council. Confirm before booking whether your property sits in a conservation area, is listed, or is covered by an Article 4 direction — each removes permitted development rights and changes the approval route.
Serving BT1, BT7, BT9, BT15 and the surrounding County Antrim area.
Find vetted trades near BelfastExtensions in Belfast: common questions
Get your Belfast extensions estimate
Upload a few photos and we'll price the job using Northern Ireland rates, then match you with up to 3 vetted professionals covering BT1.
Start your free quote