Moss, algae, and lichen growth on asphalt shingles is a sign of _____.

Moss, algae, and lichen growth on asphalt shingles is a clear indicator of high moisture levels. These organisms thrive in damp conditions and require a consistently moist environment to establish and grow. When shingles are subjected to high moisture levels, especially in shaded areas where sunlight is limited, the conditions become ideal for such growth.

Additionally, the presence of these organisms can compromise the integrity of the shingles, leading to potential damage over time. The accumulation of moisture not only supports the growth of moss, algae, and lichen but can also lead to deterioration of the roofing material itself. Therefore, recognizing the presence of these organisms can serve as an important clue for home inspectors to evaluate the overall health and longevity of the roofing system.