1. Durability and longevity: Slate roofs are known for their exceptional durability and longevity. With proper maintenance, they can easily last 100 years or more, making them a low-risk investment for insurance companies.

2. Fire resistance: Slate is a fireproof natural stone, making it an attractive option for insurance companies. In a fire, a slate roof can help prevent the spread of flames and reduce the potential damage to the property.

3. Weather resistance: Slate is also highly resistant to extreme weather conditions, including heavy rain, hail, and wind. This makes it a popular option for properties in areas prone to severe weather, reducing the risk of potential damage and costly insurance claims.

4. Low maintenance: Slate roofs require very little maintenance compared to other roofing materials. This reduces the risk of damage to the property, leading to lower insurance claims for the insurance company.

5. Energy efficiency: Slate roofs have natural insulating properties, helping to regulate the temperature inside the building. This can lower heating and cooling costs and reduce the risk of potential insurance claims for damage from extreme temperatures.

6. Aesthetics: Insurance companies may also appreciate the aesthetic appeal of a slate roof. It can add value and curb appeal to a property, reducing the risk of potential claims for damage caused by neglect or lack of maintenance.

7. High-quality standards: Slate roof installation requires skilled and experienced professionals, and the cost of a slate roof is typically higher than other roofing materials. This can indicate to insurance companies that the property owner is invested in maintaining their property to a high standard, reducing the risk of potential damage or claims.

Overall, insurance companies prefer slate roofs because of their durability, strength, and low maintenance. They offer a sense of security and reassurance that the property is well-protected, leading to a lower risk of claims and potential costs for the insurance company.