Oregon Construction Contractors (CCB) Practice Test

What is the problem with water puddling under roof shingles and underlayment after snow and ice melt?

1. It can lead to freezing issues

2. It may cause roof shingles to deteriorate

3. Water will always drain properly

4. It does not back up under the shingles

The correct answer is: It may cause roof shingles to deteriorate

Water puddling under roof shingles and underlayment after snow and ice melt primarily poses a risk of causing deterioration of the roof shingles. When water accumulates beneath the shingles, it can seep into the materials, leading to several potential issues. Extended exposure to moisture may promote mold growth, weaken the adhesive bond of the shingles, and ultimately cause them to warp, crack, or curl. As a result, the shingles can lose their protective properties and may need to be replaced sooner than expected due to this deterioration. In contrast, issues such as freezing can potentially occur with standing water but are not the main concern. Additionally, while one might assume water will drain properly, this is not guaranteed if there are underlying issues contributing to drainage problems, such as obstructions or improper installation. Lastly, the statement about water not backing up under the shingles is inaccurate since puddling indicates that the water is indeed pooling in that area, leading to the concerns related to deterioration.