The numbers
Roof Maxx says each treatment adds up to 5 years of life, and a roof can be treated again, for up to 15 years in total. Each treatment is backed by Roof Maxx's 5-year flexibility warranty: if treated shingles don't stay flexible for 60 months, Roof Maxx re-treats them at a prorated cost.
How that fits a roof's life
InterNACHI's life-expectancy chart puts 3-tab asphalt shingles at about 20 years and architectural shingles at about 30, and notes that heat and severe weather like hail shorten that. Treatment works best in the middle of that span, while shingles are still whole.
A roof treated at 12 years and again at 17, for example, can keep doing its job well past the point many homeowners would have replaced it, if the shingles stay sound.
What shortens it
Storms. Illinois averages about 2 to 2.5 days with hail a year, according to the Illinois State Water Survey, and a single bad storm can crack shingles regardless of treatment. That's why we recheck the roof before every treatment.