What should be done when cutting shingles for a roof?

When cutting shingles for a roof, it is important to round off any petal edges down. This practice ensures that the edges of the shingles do not pose a risk for water pooling or leaks, as sharp edges can disrupt the flow of water and lead to potential damages. By rounding the edges, you create a smoother surface that promotes better drainage and minimizes the risk of the shingles lifting over time due to wind or weather conditions.

In contrast, leaving edges sharp could result in water accumulation, while cutting at a 45-degree angle or trimming only the corners does not provide the same level of protection against environmental elements. Rounding edges is a tried and true method in roofing that helps ensure durability and longevity for the shingles and the roof as a whole.