Installing solar panels is a great way to save money against rising utility bills and a step toward energy independence. Before a homeowner goes solar, however, they must consider a very important question: will my roof support solar panels?
The good news is most roofs can support solar panels. There are important factors to consider though before solar panel installation. For example, the age of your roof, its structural integrity, and what materials it’s constructed with.
Tiger Solar is here to help! Our guide will walk you through everything you need to know to determine if your home is ready for a solar energy system. If you don’t find the answer here, check out our blog or contact one of our solar experts. Our team of solar panel professionals are happy to help.
How Can I Determine if My Roof Can Support Solar Panels?
Most residential roofs are designed to support 20–25 pounds per square foot, which includes weight from snow fall. Roof-installed solar panels only add 2–4 pounds per square foot, approximately. While this additional weight is well within the structural capacity of a properly built roof, there are other factors to consider.
Hire a roofing professional to evaluate the roof’s age, condition, and the materials used to build it. While the outside appearance may be obvious, don’t forget about the inside! Be sure to have the rafters and trusses evaluated as well. If you happen to be one of those more organized homeowners, you might have records from previous roof work. This documentation can help make the process easier, but we still recommend an inspection by a qualified solar professional.
What Does a Solar Installer Look for During an Inspection?
Age & Condition
The average solar panel should last at least 25 years. Roofs typically last around the same length of time, depending on the materials. If your roof is near the end of its lifespan, you may need to replace your roof before installing solar panels. A new roof can prevent the need to remove and reinstall panels later, which can be an expensive and inconvenient project. If your roof is less than 10 years old and in good condition, it’s likely ready for solar!
Building Materials
As mentioned above, the lifespan of a roof is heavily dependent upon the materials used. The most common roofing material for homes are asphalt shingles. Asphalt shingles last for 20–25 years on average, whereas metal, tile, and slate are often more durable and last longer. Weather of course can have a major impact, so if your roof has seen its share of hail, high winds, or snow, be sure to have it inspected.
Tiger Solar can install solar panels on asphalt shingles, metal, and tiles. We caution against solar panel installation on slate or wooden roofs because these materials can crack. That doesn’t mean solar panels aren’t for you though! In these cases, you might consider a ground mount installation.
Structural Integrity
Solar panels don’t add a significant amount of weight to your roof, but it is important to have a professional installer check the rafters and truss system. A structural inspection will help ensure your roof can carry the additional weight. Most residential roofs that are properly maintained should be fine, but it’s best to err on the side of caution. Like the adage, “Don’t judge a book by its cover,” a roof might look great from the outside, but a closer look might tell a different story.
What Types of Roofs Are Best for Solar Panel Installation?
Some types of roofs are better suited for solar panels than others. In addition to the material, the shape and position of your roof can also have an impact. In the section below, we explore several roof types and the common pros & cons.
Asphalt Shingle Roofs
The most common roofing material on residential roofs, asphalt shingles last around 20–25 years before needing a replacement. They also have the benefit of durability and are relatively easy to install, qualities that make for a smooth and cost-effective installation. This type of roof is the best for solar panel installation, in our opinion. The downside, of course, is that you may need to replace the roof at some point during the panels’ lifetime.
Metal Roofs
Metal roofs are excellent for solar as well. With an average lifespan of 40–80 years, metal roofs have better longevity compared to asphalt shingle roofs. In addition to natural resilience against weather events, standing metal roofs are great for installation because they allow clamps to attach to the seams without puncturing the roof. These clamps, however, can also be a disadvantage. A solar installer may need to use special clamps to prevent damage to the metal roof, not to mention the right experience.
Tile Roofs (Clay or Concrete)
The average clay or concrete tile roof can handle solar panel installations just fine. Like metal, tile roofs are long-lasting, boasting a lifespan around 50 years with proper maintenance. Solar panel installation, however, requires caution to prevent cracks to the tiles. With over 20 years of solar installations under our belts, we’ve seen our fair share of clay and concrete tile roofs. Our team has the care and expertise to make it happen.
Slate & Wood Roofs
We do not recommend installing solar panels on these types of roofs. Slate has incredible longevity—75 to 200 years—but it can be brittle and prone to breaking. Likewise, wood is also delicate. The risk of damage to these materials with roof-mounted solar panels outweighs the benefits. If you have a slate or wood roof, contact us for other options, such as a ground-mounted system.
Flat Roofs
While more common on commercial buildings, some homes also feature flat roofs which require a ballasted mounting system. This installation allows the panels to tilt at the right angle to capture the sun’s rays. A ballasted solar panel mount uses a system of weights without penetrating the roof. Common drawbacks include drainage issues, if not properly designed, and extra weight. The solar experts at Tiger Solar can conduct a structural analysis and provide the best recommendation.
Roof Orientation & Shade
The direction your roof faces and the surrounding area can also impact solar panels. For example, a southern exposure is often the most ideal orientation. East- and west-facing mounts are acceptable, but less efficient. Shade from trees, nearby buildings, and even the shape of your own roof can reduce the amount of energy your panels generate. At Tiger Solar, our job is to recommend the best position for efficient energy production.
What if My Roof Isn’t Ideal for Solar?
If a professional assessment determines your roof can’t support solar—whether the roof material is unsuitable, too shady, or has weak supports—don’t panic! There are alternatives to roof-mounted solar panels so you can still enjoy the benefits of solar energy.
Ground-Mounted Solar Systems
Your roof might not be ideal for solar panels, but your property might. With enough open space in your yard or on your land, a ground-mounted solar panel system could be the answer. Ground mounts provide just as much energy—if not more—as roof-mounted solar panels. The extra benefit to a ground-mounted system is the ability to control the tilt and maximize the sun’s energy. Keep in mind that ground mounts are often more expensive than rooftop solar panels because installation requires more equipment.
Home Battery Backups
An alternative solution to both roof- and ground-mounted systems is a standalone battery. Backup batteries store energy from the grid for later use. Time-of-use electricity rates mean you are charged more during peak hours, when demand is highest. A backup battery can offset those peak costs, especially during those hot and humid summer days. If your area is prone to blackouts, a standalone battery can keep the lights on and provide peace of mind.
Backup systems don’t need to be paired with solar, so this option is perfect if you want to save on energy bills and achieve some energy independence without the full commitment to solar.
Is Your Roof Ready for Solar Panels?
The cost of energy is rising. Aging grid technology and increased need for power is only going to continue. Solar panels offer long-term savings on your utility bills and independence.
All things considered, it’s quite likely that your roof will support panels. Even so, there are alternatives, such as ground-mounted installations or standalone backup batteries. A trusted solar installer like Tiger Solar can provide a professional assessment and present all the options.
Contact us today if you have any questions or would like a free quote for a rooftop solar system, ground-mount, and/or battery backup.