"Asphalt remains the most common roofing ... have passed UL's toughest impact-resistance test — UL 2218 Class 4," notes Dennes. "Shingles that passed this test were able to withstand the impact ...

Standard shingles are classified from Class 1 to Class 4 based on how well they withstand ... GoNano goes a step further with its molecular structure of asphalt shingles. The company has ...