Roof Maxx roof preservers keep asphalt roofs alive and well! Our secret is food-grade and completely safe for people, pets, property and the environment. Just one treatment can keep asphalt shingles going strong for another five years. And with treatments every five years, Roof Maxx can add up to 15 years of life to a roof. We're proud to be reducing the amount of construction waste in landfills and supporting a greener future with every roof we treat.