Our filler boards put quality and durability first, with wood fibre impregnated with bitumen to create high water resistance, excellent compression strength and extraordinary durability.filler boards are a staple for waterproofing applications. They rely on bitumen produced according to European or American quality standards, and are manufactured with ISO-certified processes. Our suppliers are chosen not just for quality but also their commitment to environmental sustainability, with fibre manufactured from sustainable wood sourced from cultivated forests. Quality and environmental considerations set the range of filler boards apart from the rest.