What is ThermaSheet?

ThermaSheet can be used to construct simple structures such as washstands, shower enclosures, bath panels, steam rooms and spa structures, all without the need for additional supporting timber framework.

The strength of ThermaSheet is in its complex composite construction. The closed cell structure means it has excellent properties for waterproofing both walls and floors, as well as insulating beneath underfloor heating.

This rigid foam core is reinforced on both sides with a fibreglass mesh, plus a top layer of polymerised cementitious mortar. This layering system provides ThermaSheet with excellent mechanical resistance, as well as creating an ideal surface for tile adhesive and render. Ideal surface for tile adhesive, render and screed.

Property Assessed To Rating
Xps Density DIN 53420 36 +/- 0.02 kg/m3
Thermal Conductivity EN 12167 0.033 W/m.K
Compressive Strength (10% deflection) EN 826 300 k/Pa (30 tonnes/m2
Flexural Strength ASTM C203 0.30 +/- 0.02 MPa
Water Absorption (2-day immersion) ISO 2896 0.2% by volume
Water Absorption (Capillary) DIN 53428 Zero
Water Vaopour Diffusion Resistivity (μ) DIN 52615 110-225 (μ)
Water Vapour Permeability ASTM E-96 0.028 ng/Pa.ms
Maximum Tile Loading Weight CERAM 121107 60 kg/m2
Flammability EN 13501 Class E
Impact Sound Reduction BS-ISO140 dLw=21
EU Controlled Substances Content N/A None

a Few Facts About ThermaSheet

30 Tonnes/m2

compressive strength


xps density

Class E


Key Benefits of ThermaSheet

Energy Saving

50% reduction in heat up time therefore reducing energy consumption and saving on running costs. Achieving higher temperatures as no energy absorbed by the concrete slab.

Tile Ready Service

Provides a perfect base on which to apply finishes such as tiles, synthetic renders, decorative plaster and much more. With the tile ready surface it makes construction projects easier.


Resistant to water making ThermaSheet ideal for use in areas that are subject to prolonged or permanent water immersion. Uses include, wetrooms, showers, external walls, balconies and patios, garden water features etc.


The boards are extremely lightweight and easy to manoeuvre, making projects less demanding and saving time on the job as a whole.

Enhances Floor Heating

Creating a large radiating heat surface. Heat source temperatures can be lower and creates an added benefit of the heat source spread throughout the whole room reducing heating bills.

Internal - External Use

Given its waterproofing and insulation properties, ThermaSheet is particularly useful in both internal and external wet areas exposed to moisture.

Range of Sizes

Typically, 10mm is used on the floors and 12.5mm on the walls, but our boards range from 6mm right through to 50mm to suit any project.

High Compressive Strength

More strength thanks to the extra bond between the cement mortar and the reinforcing fiber glass mesh Compressive strength rate 300k/Pa (30 tonnes/m2)

Cuts Easily

Can be cut easily using a sharp Stanley knife or a fine saw

ECO Friendly

ThermaSheet is environmentally friendly, it is CFC and HCFC free.

Render + Plaster Ready Service

This rigid foam core is reinforced on both sides with a fibreglass mesh, plus a top layer of polymerised cementitious mortar, making it an ideal surface for tile adhesive and render.

Sound Reduction

Our High Performance Construction Boards are the ideal solution where impact sound reduction is of particular importance. Designed for tiled floor areas where noise is an issue, it’s low mass helps absorb impact sound energy, giving enhanced acoustic performance.