Can Solar Panels Be Installed On Sloped Roofs In Snow Country?

Assessing Snow Load Capacity

When installing solar panels on sloped roofs in snow country, it’s essential to assess the roof’s snow load capacity. The American Society of Civil Engineers (ASCE) recommends a minimum roof snow load of 30 pounds per square foot (psf) for residential buildings in areas with moderate snowfall. For areas with heavy snowfall, such as the Rocky Mountains or the Northeast, the recommended minimum roof snow load can be as high as 60 psf or more.

To determine the roof’s snow load capacity, consider factors like roof slope, material, and age. A steeper roof slope (30° or greater) can shed snow more easily than a shallower slope. Thicker roofing materials, such as asphalt shingles or metal, can handle more snow load than thinner materials, like wood shakes or corrugated metal.

Panel Mounting and Design

To ensure structural integrity and optimal performance, solar panels should be mounted to the roof using a secure and adjustable system. Consider using a racking system designed for snow country, such as a rail-based system with adjustable clamps. These systems allow for easy panel removal and reinstallation during snowfall.

When designing the solar panel array, consider the roof’s obstructions, such as skylights, vents, and chimneys. A well-designed array should leave sufficient space between panels for snow to accumulate and shed. Aim for a maximum snow accumulation of 12 inches or less to prevent excessive panel weight and potential roof damage.

Roof Design Considerations

A well-designed roof is crucial for supporting solar panels in snow country. Consider the following design elements:

• Roof slope: Aim for a minimum slope of 30° to ensure snow shedding.
• Roof material: Choose materials with a high snow load capacity, such as asphalt shingles or metal.
• Roof structure: Ensure the roof’s structural frame can support the weight of snow and solar panels.
• Roof ventilation: Proper ventilation is essential for preventing ice dams and reducing snow accumulation.

By carefully assessing the roof’s snow load capacity, designing a secure panel mounting system, and considering roof design elements, you can safely and effectively install solar panels on sloped roofs in snow country.