• Sun delivers a combination of ultraviolet rays and heat can prematurely age a roof.

• Snow or ice that melts and refreezes (called ice damming) pushes up the roofing material and causes leaks. Ice damming can be a temporary problem that ends when the thaw is complete. Excessive amounts can damage the roof and roof structure.

• Rain is normally kept at bay by a roof. But when rain or moisture gets underneath roofing, damage can occur.

• Wind can remove any roof in the most extreme occurrence. However even minimal amounts can weaken a poorly installed roof by letting dirt and moisture get underneath.

• Moisture from condensation underneath a roof not only harms the roof and sheathing, but also can cause problems inside of the house.

• Trees provide shade to help cool a house. They also provide leaves and limbs that can fall or scrub against the roof.

• Algae and moss get a foothold on moist surfaces. Excessive growth can retain moisture and cause eventual weakening of the roofing material.

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