What is the best roofing material for solar panels?

If you're considering going solar, your roof is probably top of mind. Rooftop solar installations are very popular – they're typically cheaper than ground-mounted systems and maximize the available space on your property. But whether your roof is a good fit for solar will depend on a few factors, one of the most important being its material. Solar energy systems typically last 25 to 30+ years, so you need your roof to last long enough to support your system! This article will explain what roof materials are best for solar panels.

Many roof materials work well with solar panels, but ultimately, the best roof material will depend on your unique situation, including how much you want to spend on roofing, where you live, your aesthetic preferences, and how much you want to spend on your solar energy system. Here's a breakdown of how the best solar roof materials compare:

Comparison of best roof materials for solar

1. Asphalt shingles

Asphalt shingles are by far the most common roofing material, and for good reason: they're affordable, durable, and flexible. Asphalt roofs typically last about 12 to 30 years, depending on the quality of the shingles and where you live. Higher-quality asphalt shingles are best for solar panels because you don't want your system to outlive your roof. Due to their prevalence, every reputable installer should be comfortable installing a solar energy system on an asphalt roof. If you have an asphalt roof, your installer will drill studs into your roof and attach solar panel mounts at those locations. Your installer will then seal the space between the studs and shingles and cover it with flashing – a metal plate that prevents water infiltration – so your roof won't leak.

2. Metal roofing

If you have a metal roof, you're in great shape for solar! Metal roofs typically last 40 to 75+ years, are non-flammable, and can be energy efficient – if your metal roof is light in color, it will reflect light and heat, keeping your house cool. However, they're pretty expensive to install, and this high upfront cost can deter people from choosing metal as a roofing material. Installing solar on a metal roof requires a slightly different skill set and different racking equipment, so you'll want to choose an installer that has experience working with metal roofs. However, if your metal roof has standing seams, your installer can attach the solar panels directly to the seams, eliminating the need for drilling holes and lowering the labor costs associated with your installation!

3. Tile roofing

Tile roofs are most common in locations with hot climates or close to the ocean due to their durability. These roofs can last over a century, so you can feel confident that your tile roof will outlast your solar system (assuming it was installed within the last 50 years). However, they're more expensive than asphalt roofs (but typically cheaper than metal roofs) and can complicate your solar installation. While installing solar on a tile roof is possible, you should expect higher labor costs because your installer will likely need to remove tiles and replace them with a mounting foot and flashing because of their brittleness. Not all installers have the skill set for installing solar on tile roofs, so you should confirm that your installer is confident working with this roof material.

4. Tar and gravel roofing

Tar and gravel roofs work well with solar because they're supportive and energy efficient (gravel reflects sunlight). They'll typically last about 20 to 30 years and are easy to patch and repair if any damage does occur. However, if you have a tar and gravel roof, your roof is probably relatively flat, so you'll need some additional hardware to ensure your solar panels are pitched at the best angle. While this extra hardware can increase installation costs, it also allows you to provide optimal orientation and angle of your solar energy system, which could lead to more significant long-term savings.

In many cases, you'll want to replace your roof before going solar – but ultimately, this depends on your roof's age and material. If you have a metal or tile roof, there's a good chance you won't need to replace it to go solar. But if you have asphalt shingles or tar and gravel roofing, replacing your roof before installing solar panels is probably a good idea. If your roof material isn't suitable for solar (like if you have shake roofing), you should replace it with compatible material. As a general rule of thumb, if your roof is between five and 10 years from needing replacement, you'll likely want to replace it to go solar.

Whether your roof is suitable for solar depends on a few factors beyond its material. While you certainly don't need a perfect roof for a solar energy system to be worth it, you'll want to understand your roof's angle, orientation, and size to determine if you're a good fit for solar.

Best roof angle for solar panels

Typically, the best angle for your solar panels is about 30 degrees. However, this will vary slightly depending on where you live because you'll want your solar energy system to be angled as close to the sun as possible. So, the ideal angle is usually close to the latitude of your home, which should be between 30 and 45 degrees.

Best roof orientation for solar panels

If you live in the Northern Hemisphere, the best direction for your solar panels is south (it's north if you're in the Southern Hemisphere). A solar energy system installed on a south-facing roof will receive the most direct sunlight exposure. However, if your roof is east- or west-facing, you'll likely still generate enough savings to make going solar worth it.

Best roof size for solar panels

Typically, you'll need about 24 square feet of roof space per solar panel (enough for the solar panel plus about 25 percent extra space), and an average home needs between 20 and 24 solar panels to offset utility bills with solar fully. So, the best roof size for solar panels generally lies between 480 and 580 square feet – though this will depend on your household's energy consumption and the efficiency of your solar system.

What roof material isn't suitable for solar panels?

If you have a wood or slate roof, you likely won't be able to install a rooftop solar energy system without replacing it. These roof materials are quite brittle, making them susceptible to breakage, and wood roofs are flammable, presenting a fire risk. 

What roof color is best for energy savings?

Lighter color roofs better reflect sunlight, which means they don't absorb as much heat and can keep your house nice and cool. So, if you have a choice in roof color and want to maximize your energy savings, it's best to go with a light-colored roof, like light gray or tan.

How much does a roof replacement cost?

On average, it will cost about $8,000 to replace your roof – however, this will vary significantly based on your current and new roof material, where you live, and the complexity and size of your roof.

Ready to start shopping for solar? On the EnergySage Marketplace, you can compare multiple quotes from pre-approved solar installers to find a system that meets your needs at the right price. If you have any questions about whether your roof is suitable for solar or about your quotes in general, be sure to connect with your free Energy Advisor, who can help guide you through the installation process. If you're not a good fit for home solar, visit our Community Solar Marketplace to explore open projects near you.