What is a typical sign that a roof needs replacement?

The presence of moss and algae is a typical sign that a roof needs replacement due to the implications these organisms can have on the roof's integrity. When moss and algae grow on a roof, it often indicates that moisture is trapped on the surface, leading to potential deterioration of the roofing materials. Over time, this moisture can compromise the roof, causing wood rot, shingle deterioration, and ultimately, leaks. The accumulation of these organisms can accelerate the aging process of the roof and may signal that it is retaining moisture and not shedding water as effectively as it should.

In contrast, local weather conditions and infrequent maintenance can influence the longevity of a roof but are not direct indicators of its need for replacement. Discoloration of downspouts may suggest other issues such as poor drainage or rust but does not specifically imply the condition of the roof itself. Hence, the presence of moss and algae stands out as a clear, immediate sign for homeowners to consider a roof replacement to avoid further damage and costly repairs.