Mineral wool EWI · Northern Ireland
Mineral wool external wall insulation in County Down
Planning mineral wool external wall insulation anywhere in County Down? We cover towns including Bangor (County Down) and Castlereagh, and check planning and building control for each address. Older solid-walled homes in County Down can suit a vapour-open mineral wool build-up better than foam; the survey checks the wall first.
- Free survey and fixed written price
- Guide price from £125 per m² + scaffold, 0% VAT
- Planning and building control checked for Northern Ireland
Free survey in County Down
Tell us the postcode and what you need.
Included as standard
- Finished in mineral or silicone render, or brick slip
- Heavier than EPS, so more fixings and careful handling
- Non-combustible board (typically Euroclass A1 or A2-s1,d0 as part of the system)
- Vapour-open, so moisture in solid walls can dry outwards
- Better sound reduction than foam boards
Homes and walls in County Down
Northern Ireland has many rendered and pebble-dashed homes, older solid-walled rural houses, and estates built by the Housing Executive.
Exposure to wind-driven rain varies across County Down: sheltered town streets fare better than walls on high ground or facing the prevailing weather, and the render, beads and cill details are chosen with that in mind.
On blocks and taller buildings in County Down, mineral wool is the default because of the fire guidance for external walls.
- Nation
- Northern Ireland
- Region
- Northern Ireland
- Towns covered
- Bangor (County Down), Castlereagh, Newtownards, Newry, Banbridge, Holywood, Downpatrick
- Guide price
- From £125 per m² + scaffold · 0% VAT
Northern Ireland: planning and regulations
In Northern Ireland, permitted development is set by the Planning (General Permitted Development) Order (NI) 2015. Changing the external appearance of a house may need permission, and conservation areas, flats, commercial buildings and listed buildings need planning permission or listed building consent. Check with your council's planning office.
Insulating external walls is building work under the Building Regulations (Northern Ireland) 2012, handled by council building control, with Technical Booklet F1 covering conservation of fuel and power in dwellings.
Technical Booklet E sets the fire-safety guidance for external walls. On taller buildings we use non-combustible mineral wool systems and confirm the classification with building control.
Why choose mineral wool over EPS?
Two reasons come up most: fire and moisture. Mineral wool doesn't burn, which is why guidance for taller residential buildings points to non-combustible external wall materials. It is also vapour-open, so a solid wall that holds some moisture can keep drying outwards through the insulation and render.
The trade-offs are weight and cost. Slabs are denser, need more fixings and take longer to install, so the price per m² is higher than EPS.
Mineral wool external wall insulation prices in County Down
| Item | Guide price | Notes |
|---|---|---|
| Mineral wool + mineral or silicone render | £125–£170 per m²0% VAT | Excluding scaffold |
| Mineral wool + brick slip | £195–£260 per m²0% VAT | Heavier slip systems need extra fixings |
| Three-bed semi, full house | £11,800–£20,2000% VAT | 80–100 m² of wall, including scaffold |
Confirmed by a fixed written quote after survey. 0% VAT: installing insulation in a home is zero-rated until 31 March 2027, so these figures are the total; 5% applies from 1 April 2027.
What happens next
Tell us about the property
Use the quote tool or form, or call. Photos help.
Free survey
We measure, check the walls and confirm approvals.
Fixed written quote
System, details, access, exclusions and VAT in writing.
Installation
Scheduled for suitable weather, with a clear programme.
Mineral wool EWI in County Down: questions
Is mineral wool needed for a bungalow?
Rarely for fire reasons. It may still be chosen on a damp-prone solid wall where a vapour-open build-up is wanted.
Is mineral wool better than EPS?
Not always better — different. Mineral wool wins on fire performance, breathability and acoustics; EPS wins on cost, weight and thinner boards for the same U-value. The wall, the building height and your priorities decide it.
Can mineral wool EWI have a brick finish?
Yes. Brick slips can be bonded over mineral wool systems designed for them, with additional fixings for the extra weight.
Do you cover all of County Down?
Yes. We survey and quote mineral wool external wall insulation across County Down, including Bangor (County Down), Castlereagh, Newtownards, Newry, Banbridge.
Do I need planning permission in Northern Ireland?
In Northern Ireland, permitted development is set by the Planning (General Permitted Development) Order (NI) 2015. We check your address before quoting.