Ground to floor solutions and effective concrete floor insulation prevent unnecessary heat loss in buildings. They can help to maintain a comfortable temperature and improve energy efficiency.

Without under slab insulation, the direct contact from the floor to the ground makes it an easy route winter cold to get in.

Insulation can be installed above or under concrete slabs to improve thermal efficiency, with around 30 percent of all heat in homes lost through the floor. 

Why do we need ground to floor insulation?

Concrete slab insulation between the ground and the floor is vital to create a comfortable living environment. Not only does it make a building more energy efficient, it also helps to create cosy, comfortable and habitable conditions for people living or working there.

Some of the main benefits of under slab insulation include:

  • Energy efficiency – helps to trap heat in and reduce energy bills substantially.
  • Compressive strength – able to withstand heavy loads, which make it ideal for insulating private and commercial buildings.
  • Fire safety – ROCKWOOL insulation is fire resilient up to 1000 degrees1.
  • Sustainability – solid floor insulation lasts for the lifetime of your building.

Calculator and savings

Costs and savings will vary depending on several different factors. But the initial cost of insulation will be outweighed by the savings made over time on energy bills.

Installing concrete floor insulation can significantly reduce heating costs over a building’s lifetime. The slabs can also be used again in other projects if the building is demolished, making them an investment for future projects.

Concrete insulation is placed underneath a floor in between the building’s foundations. Calculating the size of the surface area will directly provide the m2 needed. The m2 measurement of floor equals the m2 of insulation required.

For more information, a locally available U-value calculator can help determine the insulation type and thickness required for your project.

Construction Site: Neat Clean Crawlspace, Floor Joists, and Pony Wall - crawl space design and installation process
A well-insulated floor contributes to the comfort in a building, keeping the floor temperature at a steady level.

Roger Peeters

ROCKWOOL Group Product Manager

Sustainability and energy efficiency

ROCKWOOL insulation products are fully recyclable. Since ground to floor slabs are usually ‘loose laid’ on the ground, the slabs can easily be taken out and reused.

Ground to floor insulation is mainly used in new build projects – and one of our company’s key values is helping to make our towns and cities as sustainable as possible for future generations4.

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Financial support

Local schemes and tax incentives may be available in your country to help finance your project. Contact our local offices for more information.

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How much ground to floor insulation will I need?
Does floor insulation make a difference?
Can I use ROCKWOOL insulation under a concrete slab/floor?