Sika is the No. 1 world leader in roofing material technologies which include: proven high-quality flexible membranes (PVC and FPO) with a long track record which can be either mechanically fastened or adhered to substrates in exposed roofing systems or be loosely laid under ballast; liquid membranes based on high-performance polyurethanes (1-Component PU powered by Moisture Triggered Chemistry) allowing even easier application by hand or machine on difficult roofs and details.