Extra protection against weather and storms. Use WeatherLock® G Granulated Self-Sealing Waterproofing Barrier on the entire roof deck as a secondary water barrier under asphalt shingles, wood shakes and quarry slate roof assemblies. This provides additional security against leaks caused by storms, wind-driven rain and shingle blow-offs. WeatherLock® G also has a taped selvedge edge to offer improved seal between courses and peace of mind that your roof has an extra layer of protection.