Bitumen impregnated compressible fibre filler board


Polyboard is a compressible bitumen impregnated fibre board for expansion joints. the impregnated softboard is made from natural wood fibres chips and proprietary materials, mechanically reduced to fibres which are then pressed to form a continuous sheet. Bitumen is incorporated into the board  during manufacture to improve its moisture resistance and durability.


  • Multi-purpose bituminized softboard made from natural wood fibres for roof, wall and floor in concrete and timber constructions.
  • Excellent recovery after 50% compression
  • Good thermal insulation properties
  • Available in various bitumen contents
  • Easy to install

This TDS is applicable for the United Arab Emirates only. Please contact your local Polybit sales office for the available TDS in your region

Step by step

Specification Compliance

Wood fibre insulating board produced complies with the pertinent type requirement of ASTM D 1751 (compression, extrusion and recovery only). Production standard as per din en 13986 /din en 622-4

Installation Procedure

When used to form movement joints in in-situ concrete, POLYBOARD can be positioned next to the shuttering before casting or can be bonded to the adjacent concrete with an appropriate adhesive. the softboard must be protected on external faces by a compatible weather resistant sealant. Polyboard up to a thickness of 19mm can be cut using a stable knife and a guide bar for a straight edge after cutting. to avoid tearing in the reverse face, the cut should be made onto a flat rigid backing material. Boards thicker than 19mm should be cut with a portable electric circular saw.


Polyboard can be fixed to protect waterproof membrane with a suitable adhesive like Bitubond N or by suitable approved mechanical fixing methods.