The core of Sika’s plaza deck and green roof success lies with our high quality, durable Sarnafil G476 membrane. It is a specially formulated fiberglass reinforced thermoplastic sheet compounded to remain watertight in buried environments.

The waterproofing membrane’s resistance to ponding water, along with its dimensional stability and elongation characteristics, make the G476 an excellent sub-grade membrane that thrives in constant dampness, high alkalinity, and exposure to plant roots, fungi, and bacterial organisms, as well as varying levels of hydrostatic pressure.

G476 is also bright orange which makes it easy to identify and inspect during and after installation.

Alpha Alabama Apartments


  • Durable and highly puncture-resistant
  • Sustainable membrane has proven to last under the harshest of buried conditions
  • Highly resistant to bacterial growth
  • Installation possible in every climate condition
  • Used successfully under green roof and plaza deck applications
  • Produced with an integral fiberglass mat carrier sheet for exceptional dimension stability
  • Low coefficient of thermal expansion and contraction
  • Hot-air welded seams are impervious to moisture infiltration
  • Membrane does not absorb water and is thereby unaffected by ponding water
  • Easily installed over irregular or existing waterproofing


Waterproofing membranes must be tough and highly puncture-resistant to withstand potential damage during and after installation.  Highly puncture-resistant, the Sarnafil G 476 waterproofing membrane and its bright orange color make it easy to identify and inspect to maintain high levels of quality assurance and control during installation.  The G 476 membrane is available in a range of thicknesses to match your application, overburden type, and specific project requirements.


Many waterproofing membranes are not resistant to root penetration. They fail due to root infiltration into the field seams and flashings. Roots are very aggressive and can penetrate certain types of waterproofing materials. The waterproofing system must be resistant to roots and should not deteriorate in damp environments. The Sarnafil G 476 membrane is inherently root and algae resistant and requires no additional barriers to be added to the system. Sarnafil membranes have passed the most stringent European tests for root resistance including both the German FLL and the Swiss SIA 280 standards. The FLL standard test exposes the waterproofing membranes to 4 years of accelerated root growth.


Faulty seams and details are a common source of leaks in green roofs. Some waterproofing membranes use sealants, adhesives or tapes to secure the seams, but because the Sarnafil membrane is thermoplastic, seams and flashings are welded together using Sika’s automatic hot-air welder, the Sarnamatic. When welded together, the sheets become one monolithic layer of material impervious to moisture infiltration.