Protherm Overlay Panel

The Hetta Protherm overlay panel is a lightweight construction board designed for use with tiles, cement-based screeds and synthetic renders. It is manufactured from high density extruded polystyrene with a reinforced cement coating on the top and bottom surfaces providing excellent impact and compressive strength.

The Protherm panel can be cut using conventional tools and has good bonding properties for direct application of cement-based tile adhesives.

Note: Solvent based products must not be used.



The easy to install panels are glued directly to existing concrete or any flat surface, the textured surface allows for excellent adhesion.

Maximum Pipe Lengths – 80m

The boards are Ideal for use in wet areas such as bathrooms and where there is exposure to moisture, for soft floor finishes, it is essential to cover the panel with a minimum of 10mm thick flexible, cement-based levelling screed. For wood panelling and wood laminate, the panel should be covered with a minimum of 7mm thick flexible, cement-based levelling screed. The Protherm panels are not suitable for laying directly onto joists and must have a supporting floor surface such as plywood, floor grade chipboard or similar.

Health & Safety:
Use normal respiratory and eye protection when cutting or machining Fumes from thermal decomposition may cause temporary irritation, no special label requirements during transport


Specification & Technical Details

Pipe Diameter


Thermal conductivity

0.034 W/mk

Pipe centres



Cement Reinforced Surface XPS

Water Absorption


Compression Strength

400 Kpa

Temperature Range

-50 deg to 75 deg Centigrade

Fire performance

BS 476 / EN13501-1 Class 0 / Euroclass E

Sound Reduction

BS EN ISO 10140-3 19dB ( 6mm )


2.48 kgs

Panel Dimensions
1200mm x 600 mm x 16mm