Grassflex tiles are manufactured with a recycled rubber granulate base that is soft and safe for use on waterproofing membranes. Grassflex tiles are also manufactured with drainage channels on the underside. As the tiles are water permeable up to 250mm per hour (EN 1176) they allow rain water to flow through the tiles and off the waterproofing through the drainage channels on the underside.
Artificial grass is occasionally used on flat roof and balcony applications. In most cases consideration is not taken as to how the grass should be bonded to the waterproofing and whether or not the artificial grass can damage the waterproofing.