A method and a kit for rejuvenating shingles of a roof is disclosed. The method comprises: applying a first composition on an outer surface of said shingles for softening and making them flexible; coating the first composition with a second composition; and applying over the second composition a third composition configured to mechanically reinforce the softened flexible roof shingles. The second composition is configured to provide adhesion between the first and third composition. The rejuvenated asphalt shingles according to the present invention show similar impact resistance, lower granule loss, resistance against wind, and no adverse impact by fungi compared to new/original shingles. The method and kit as described herein allows rejuvenating the shingles, saving as such time and important costs compared to the entire replacement of the old shingles by new ones.