Ground Mount vs. Roof Mount Solar Panels: Which is Best?
Should you mount your solar panels on your roof, or build a dedicated ground mount for your array? In this article, we’ll compare the differences between roof mount vs. ground mount solar panels to help you decide which option is best for your solar project.
Here's a quick summary for busy folks:
Roof-mounted solar panels conserve space on your property, and they are less expensive to install.
Ground mounted solar panels take up more space, but it’s easier to build them at the perfect location to get the most production from your array. They are also more accessible for routine cleaning and maintenance.
Roof-Mounted Solar Panels: Pros & Cons
- Lower installation cost
- Most space-efficient option
- Easier to permit
- Must climb on roof to install & maintain panels
- System design limited by roof size & orientation
Why Choose Roof-Mount Solar?
Roof-mounted solar panels are the go-to pick for most residential solar projects. Since many residential properties have limited yard space, homeowners often prefer to build their systems on their roof to conserve real estate.
Roof-mount systems are also simpler and cheaper to install, making them the default choice for a majority of residential installations.
Lower Installation Costs
The great thing about roof-mounted solar panels is that they take advantage of the existing support structure of your home to act as a foundation for your solar array.
Most homes (especially newer homes) are over-engineered to handle the additional weight of solar panels. By securing your racking structure to your roof rafters, you can bypass the need to build a separate load-bearing foundation for your array. This will save you some money on the installation side, both in materials and cost of labor.
Please note that this may not be true for older properties, which may have been built to less strict standards, and have likely suffered some wear and tear over the years. As part of the process of going solar, we recommend a structural analysis to ensure your rooftop can support the weight of solar panels with no issues.
If space is at a premium on your property, it makes the most sense to opt for roof-mounted solar panels. After all, what else are you using that space for? It’s smart to build your system on your roof and save the yard space for something more useful.
Disadvantages of Roof-Mount Solar
While roof-mount arrays are common for residential solar projects, they aren’t always the best option. Here are a few things to look out for.
Proper orientation is key to getting the most out of your panels. Solar arrays produce the most overall power when panels face South, so that they point directly at the sun in the middle of the day. To maximize energy savings, it’s often smart to rotate them toward the West to generate power later in the day. This helps offset higher time-of-use (TOU) rates, as the utility bills more during peak usage hours (around 4-9pm).
With rooftop solar, it’s not likely that you’ll get the “perfect” orientation for your system. Your choices are limited by the build space available on your roof.
However, rooftop solar is still perfectly viable in less-than ideal conditions. Solar panels on West- or East-facing rooftops still outperform utility power by a wide margin. But a ground mount array may be more appealing if you want to get the orientation just right.
Limited Roof Space
Not all rooftops have the space to accommodate a solar power system. Solar panels are quite large (about 3.5 feet wide and 5.5 to 6 feet tall, depending on which you choose), and the average American home may need about two dozen panels to offset their bill. Your needs will vary based on your energy usage -- check out our solar calculator for a personalized estimate.
Depending on the size/shape of your roof, as well as placement of things like vents, air conditioning units and fire line setbacks, your build space on your roof may be limited. In this case, you may need to compromise on a smaller array, or move your plans to a ground mount (if feasible) to fully meet your energy needs.
While rooftop solar panels make the most of unused space, they’re also harder to access for installation and maintenance. We recommend roof-mounted solar panels to people who are physically capable and comfortable climbing on their roof. You’ll need the proper safety equipment to do the work.
We suggest cleaning solar panels once a year to keep them free from dust and debris that could impact their production. It’s certainly easier to clean and maintain ground mount systems than it is to break out the ladder and safety harness each time you want to care for a rooftop array.
Ground Mount Solar: Pros & Cons
- More accessible to install & maintain
- Optimize your panels for maximum production
- More costly to install
- Takes up space on your property
Why Choose Ground Mount Solar?
A ground mount solar array makes sense if you want to optimize your system for maximum production. It also offers easy access for ongoing care.
Ground mounts are particularly favored in large-scale installations. They can make use of larger panels and ensure the array is oriented to optimize production.
Optimize Your System’s Output
The main draw of ground-mount arrays is that you can build your panels in the best available location and orient them to optimize your system’s output.
If you’d like to produce as much power as possible, it’s best to face your panels due South. That will give the panels as much exposure as possible to the sun throughout the day.
If you’d like to maximize the money you save, we’d recommend rotating those panels to the Southwest to shift your peak production window later in the day. Many utilities bill higher electricity rates from about 4-9pm, when folks come home from school/work and the demand on the grid is highest. Rotating panels Westward allows you to generate more power when rates are highest, saving you more money.
Another custom ground mount option is a pole mount, which is designed to lift panels higher off the ground. Pole mounts are great in snowy environments when you want to make sure your array is elevated above the snow banks that may gather beneath the panels in the winter months. Pole mounts are also easier to install on steep hills, where it’s more complicated to anchor a standard ground mount into the earth and ensure the racking is level.
No ladder or safety harness required. Ground mounts are much easier to access, which can make a huge difference if you plan to install your solar panels yourself and play an active role in maintaining your system.
Disadvantages of Ground Mount Solar
The key disadvantage of ground-mount systems (and the reason most folks choose a roof-mounted array) is the higher cost of installation.
Ground mount systems require you to build a separate foundation to support your array. You will incur extra costs in racking materials, and there’s extra labor involved to dig holes, pour concrete footings and build the foundational structure.
You will also need to dig a trench from the array to the service panel, so that you can run conduit and wiring at least 18” underground (required for code compliance). That usually means renting high-powered machinery, which drives up installation costs.
All else being equal, roof mounts are much more budget-friendly than ground mount systems to install.
Complex Permitting Process
In most jurisdictions, ground mount systems are considered “new construction,” which usually means a more complex permitting process (and higher permitting fees).
Your local building authority will ask for additional information on your permit, like structural drawings, property line setback requirements, and load-bearing calculations by a professional engineer.
Though ground mounts may be more involved to permit, that shouldn’t stop you from moving forward with a ground mount system if that’s what you prefer. We regularly help customers secure ground mount permits as part of our solar permit service, which comes with a full money-back guarantee if your permit doesn’t get approved.
Ground Mounts Take Up Valuable Real Estate
Ground mount arrays take up space on your property that may otherwise be used for more interesting things, like an outdoor grilling area, a tool shed or a swimming pool. If you live on a smaller plot of land, it’s harder to justify a solar system eating up space in your yard.
Ground mounts make a lot more sense for more larger properties, where there is more space to build without feeling cramped. If you’re not sure whether a ground mount array would fit on your property, feel free to reach out to us for a free solar design consultation. We use satellite imagery and professional design software to accurately show how your solar system will fit on your property.
Interested in Going Solar?
At GoGreenSolar, we provide solar equipment, design and permitting services for residential and commercial solar projects. If you’re ready to go solar, connect with us for a free design consultation. We can help you find the perfect solar kit, or design a custom kit that is tailored to suit your needs.