Illinois Roofing Practice Exam

Which element is most likely to need enhancement when installing valleys in areas prone to regular freeze-thaw cycles and accumulations of ice and snow?

1. Underlayment

2. Ridge vents

3. Open valleys

4. Gutter guards

The correct answer is: Open valleys

The likelihood of needing enhancement in valleys during installations, especially in areas that experience freeze-thaw cycles and significant accumulations of ice and snow, makes the choice of open valleys particularly critical. Open valleys are typically constructed using metal flashing in a channel between two slopes of the roof. During freeze-thaw cycles, the melting snow can flow into the valley, and if the drainage is inadequate or obstructed, it can lead to ice dams. Ice dams result when melting snow flows down the roof but refreezes in the valley or gutter, obstructing further water drainage. This situation can cause water to back up under the shingles and lead to leaks and water damage inside the home. Therefore, enhancing the design and materials used in the valley, such as ensuring proper installation of the flashing and considering snow retention features, can significantly mitigate these risks. It is essential to create a channel that can efficiently direct water away from the roof system to prevent overflow and the potential damage associated with ice accumulation. The other components listed, such as underlayment, ridge vents, and gutter guards, while important, do not directly address the specific challenges faced by open valleys in freeze-thaw conditions.