Slate shingles are primarily used for roofing due to their:

Slate shingles are primarily valued for their durability. This high-quality material has a long lifespan, often lasting over 100 years when properly maintained, which makes it an ideal choice for roofing. The natural stone is resistant to weather extremes, including heavy rain, snow, and wind, and is also fire-resistant and rot-resistant. This resilience leads many homeowners to choose slate shingles for long-term investment in their roofs, despite their higher initial cost compared to other roofing materials.

While other factors such as weight and installation ease are considerations in roofing choices, they do not outweigh the primary advantage of durability that slate shingles offer. Weight, for example, is a characteristic of slate but can present challenges during installation and requires careful structural consideration. Lower costs or ease of installation might appeal to some, but they are not the primary reasons for the preference of slate in roofs.