Bitumen Membranes

Heavy Grade Hydroseal

Heavy Grade Hydroseal is a thick, inert fibre reinforced solvent cut bituminous mastic. It is easy to use and adheres to all dry, clean surfaces. Heavy Grade Hydroseal is alkali and acid resistant, and when dry it will not contaminate drinking water. Specially designed to be trowel applied to any surface. It forms a tough skin quickly then dries slowly beneath the surface.

Key Benefits Summary:

  • Low Cost
  • Will not slump at temperatures up to 70oC
  • Will not contaminate drinking water


  • Heavy Grade Hydroseal is specially formulated for waterproofing and sealing cracks, laps or joints and fixings on new or old structures of metal, concrete and timber
  • Domestic, Industrial and Commercial Buildings: Roof sheetings, flashings and cappings, box and valley gutters, downpipes, under screws and washers
  • Rural Applications: Sheds and other buildings, water tanks and troughs
  • Marine Work: Sealing against water, drafts and fumes, bedding in deck timber, sealing fixed windows