Floor Insulation

Installing floor insulation at ground floor level can transform the comfort levels of the building. With up to 15% of a building’s heat loss occurring through uninsulated ground floors, well insulated floors will significantly reduce heating costs over the lifetime of the building.

Floor Insulation Options

PIR insulation boards like the Mannok range are among the most thermally efficient and commonly used floor insulation products.

Mannok’s EPS insulation boards provide a cost-effective alternative to PIR insulation boards for floor applications, as it is easier to increase the thickness of insulation used in the floors in order to achieve the same thermal performance.

Floor insulation boards, whether you opt for PIR or EPS insulation, are lightweight and easy to handle and fit. These rigid insulation boards comply to all relevant industry standards and can help achieve excellent thermal performance.

Floor Insulation Installation

It is usually enough to insulate the ground floor of a building, unless there are other floors positioned above an unheated space, such as a garage.

How to install floor insulation boards will be dependent on the building’s type of floor construction.

The two main types of floor construction are solid ground floors and suspended floors and the installation method for floor insulation will differ for each construction type.

Solid ground concrete floors can be insulated below or above the ground bearing slab. Where a timber floating floor is laid on top of the concrete slab, insulation is fitted above the slab.

Suspended floors use either timber or beam and block construction. For beam and block floors, the insulation is laid above the ground bearing structure and for suspended timber floors, the insulation boards are fitted between the timber joists.

Floor Insulation Key Considerations

Whatever the floor construction type, there are a number of important considerations for your floor insulation:


The floor insulation specified must be of the correct standard to support the anticipated load which will differ for domestic and commercial buildings. Our PIR insulation and EPS insulation product guides provide information on product strength to help determine the correct floor insulation for the application.

Thermal performance

Thermal performance will be determined by the type and thickness of floor insulation boards used. Our U-value calculator will help calculate the insulation thickness to achieve the desired thermal performance.

Thermal bridging

Thermal bridging, or cold bridging, occurs where there is a break in insulation in the building envelope, which can result in significant unnecessary heat loss. Floors should be designed to avoid thermal bridging issues at the key floor to wall junction. For some floor construction types, perimeter insulation should be used to combat thermal bridging issues.

Need technical support?

For help and advice on any of our products and how they might fit your needs please contact our Technical by Mannok team.

  • Floor Insulation
  • Pitched Roof Insulation
  • Flat Roof Insulation
  • Wall Insulation