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County Antrim · Northern Ireland

Underfloor insulation in County Antrim

Underfloor insulation fits mineral wool or rigid boards between the joists of a suspended timber floor, supported on netting or battens, so cold air from the ventilated void below stops chilling the room. Our County Antrim coverage includes Belfast, Lisburn, Newtownabbey and the towns around them.

Lifted floorboards showing insulation fitted between suspended timber floor joists

Free survey in County Antrim

Tell us about the property and we will arrange a free survey and a fixed price.

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Underfloor insulation across County Antrim

We cover 7 towns in County Antrim, including Belfast, Lisburn, Newtownabbey, Carrickfergus, Ballymena and more.

Small measures like this are often among the cheapest per pound saved, and they suit County Antrim homes of every age. We check ventilation as carefully as insulation in County Antrim homes, because both matter for keeping a house dry.

Building control in Northern Ireland

In Northern Ireland, inserting insulation into an existing cavity wall needs a building control application to your council before the work. We make sure the application route is agreed and confirmed in writing before any drilling starts.

Funding in Northern Ireland

  • The Affordable Warmth Scheme, run with the NI Housing Executive, helps owner-occupiers and private tenants with a total gross household income under £23,000; cavity wall insulation is a priority measure where suitable.
  • The NI Sustainable Energy Programme funds energy efficiency schemes through participating providers.
  • ECO4 does not apply in Northern Ireland.

Sources: Building Control NI: frequently asked questions; Belfast City Council: what are the building regulations; NI Housing Executive: Affordable Warmth Scheme; Utility Regulator: NI Sustainable Energy Programme.

Keeping the void ventilated

Air bricks under a suspended floor must stay clear so the timbers stay dry. Insulation goes between the joists, not across the void, and gaps at skirtings are sealed to stop draughts.

What is included

  • Floor void inspection
  • Insulation between joists
  • Draught sealing at skirtings
  • Boards relaid

Underfloor insulation prices in County Antrim

Underfloor insulation guide prices
Underfloor insulation guide pricesGuide price
Suspended timber floor, typical room£795–£1,495
Whole ground floor£1,995–£3,995

No VAT is charged on installing insulation in homes until 31 March 2027 (then 5%). Guide ranges only: the fixed price is confirmed in writing before any work starts, and anything that could not be seen at survey is agreed with you first.

The steps for underfloor insulation in County Antrim:

  1. Tell us about the property

    Postcode, property type and what you would like done.

  2. Free survey

    Access, condition, existing insulation and ventilation checked.

  3. Written result and price

    What we recommend and a fixed price before any work.

  4. Work and tidy-up

    Fitted at an agreed time, with ventilation kept clear.

Last reviewed 19 October 2026.

Underfloor insulation in County Antrim: questions

Do you cover all of County Antrim?

Yes. We cover 7 towns across County Antrim, including Belfast, Lisburn, Newtownabbey and Carrickfergus, and the villages around them. Island and remote addresses are surveyed by arrangement.

Do you work on rented homes in County Antrim?

Yes. Landlords and agents in County Antrim can book batch visits, and work is arranged around tenants.

Is there VAT on underfloor insulation in County Antrim?

Installing insulation in a home is currently zero-rated for VAT until 31 March 2027, then 5%. Commercial buildings are standard-rated.

How much does underfloor insulation cost in County Antrim?

Our guide ranges for underfloor insulation are shown on this page. The fixed price for your County Antrim property is confirmed in writing after the survey, before any work starts.

Underfloor insulation in nearby areas

Book a free survey in County Antrim

Free survey with an install quote. Written result. Fixed price before any work.