Calculate your external wall insulation cost
External wall insulation cost per m² in Belfast
External wall insulation by property type in Belfast
The UK figures are current property examples; the city column applies the same moderated 18% regional weighting as the live calculator.
UK £5,000–£7,000 · avg £6,000£4,900–£6,850 · avg £5,900
UK £6,000–£10,000 · avg £8,000£5,900–£9,800 · avg £7,850
UK £14,000–£20,000 · avg £17,000£13,700–£19,600 · avg £16,650
UK £15,000–£21,000 · avg £18,000£14,700–£20,600 · avg £17,650
UK £20,000–£30,000 · avg £25,000£19,600–£29,400 · avg £24,500
Current UK system benchmarks
What can change a real Belfast quote?
- External wall area
- EPS, mineral wool or board system
- Render or cladding finish
- Scaffolding
- Gutter and pipework changes
- Existing wall condition
Local planning considerations
Northern Ireland has different policy and grant arrangements from Great Britain, so scheme-specific calculator assumptions should be checked carefully.
- Northern Ireland regulations, approvals and support schemes should be checked independently from England, Wales and Scotland guidance.
- Regional material supply, specialist-trade availability and travel can affect individual quotes beyond the broad model factor.
- For major refurbishment, keep surveys, remedial work and compliance costs separate from visible finish upgrades.
How the regional model works
The live external-wall-insulation calculator uses only 18% of the broad Northern Ireland regional difference because insulation boards, fixings and render systems contain a substantial nationally priced material component. The resulting Belfast EWI factor is 0.980× and is applied to the current £150–£200 per m² installed benchmark.
Sources
External Wall Insulation Cost: 2026 UK Guide
Published / checked: July 2026
Used for: Installed external-wall insulation cost-per-m² and property-type ranges
Frequently asked questions
How much does external wall insulation cost in Belfast in 2026?
The current UK installed benchmark is £150–£200 per m², averaging about £175 per m². Using the same moderated regional factor as the live calculator gives a Belfast planning rate of about £147–£196 per m².
How much is external wall insulation for a semi-detached house in Belfast?
The current UK semi-detached example is £14,000–£20,000, averaging £17,000. Applying the moderated Belfast model gives about £13,700–£19,600, with a modelled midpoint near £16,650.
Why is the Belfast EWI adjustment smaller than the broad regional factor?
External wall insulation contains a large material and system component, so the live calculator applies only 18% of the broad regional difference rather than treating the entire installed price as locally variable labour.
What can make external wall insulation more expensive?
Wall repairs, scaffolding, architectural detailing, moving rainwater pipes and services, premium finishes, difficult access and larger exposed wall areas can all increase the final quote.