When most people think about installing solar panels, the first thing that comes to mind is a pitched roof.
Roof pitches of at least 25 degrees are ideal for the installation of photovoltaic systems because they keep the panels from getting too hot and help them catch more sunlight.
However, not all properties have this type of roof. Some homes or businesses may have a flat roof instead of a pitched one. This is often the case for smaller buildings with less expensive construction, properties that need to conserve space, or simply not part of the building design.
Don’t let that stop you from going solar though! Installing solar panels on a flat roof is possible and even beneficial in some cases. When you’re ready to take the next step towards going solar, read on to learn more about your options when it comes to flat roofs and solar panels.
How do solar panels work?
Photovoltaic cells, which produce electricity when exposed to light, make up solar panels.
Panels are either mounted on the roof or put on the ground itself, where they’ll receive less shade from trees and other plants.
As the sun’s rays hit the cells in the panels, the photovoltaic effect kicks in and electrons are knocked loose. An electric current flows through wires from the panels to your home’s electrical system, powering appliances and other devices. This is how solar panels create green energy.
Panels can be installed in a grid pattern or as a single unit. They can also be mounted on a wall, as long as it gets plenty of sunlight throughout the day.
Advantages of installing solar panels on a flat roof
- Less expensive than pitched roofs
Installing solar panels on a flat roof is cheaper than doing so on a sloped roof.
This is because the panels themselves are smaller, meaning you’ll need less of them to generate the same amount of power. The smaller panels also make it easier to install them on a flat roof, which can save you even more on the installation costs.
- More durable than pitched roofs
As mentioned above, pitched roofs aim to withstand larger amounts of water caused by rain, snow, and ice.
Flat roofs, on the other hand, don’t have to deal with these weather conditions as often, making them a more durable option for solar panels. Depending on the area you live in, not having to worry about snow and ice on your panels could extend their lifespan substantially.
- Can be more accessible
If you’re on a lower floor in an apartment building, pitched roofs can be hard to reach, depending on the building structure.
Difficulty in getting panels installed makes flat roofs an attractive option.
- Reduced shading on panels
Angled roofs aim to catch the most sunlight possible while flat roofs are less noticeable and easier to shade. If there are trees or other plants around your home, adding a panel to a flat roof can help keep them shaded to a minimum.
Disadvantages of installing solar panels on a flat roof
- Less power than pitched roofs
Flat roofs go without saying that they aren’t as effective in catching the sunlight as sloped roofs because of their angle. They’re also much easier to shade, which means you’ll be getting less power from the system overall.
- Panels can get hotter
As mentioned above, pitched roofs aim to catch and retain as much heat as possible. This is intentional, as it helps the panels work more efficiently. While this is helpful on gable roofs, it can cause flat panels to overheat during certain seasons.
- Panels may be less aesthetically pleasing
If you have a nice-looking home with a pitched roof, adding photovoltaic panels may help you go solar. Adding panels to a flat roof may change the aesthetic of your property, however, and you may have to consider this before making the decision to go solar.
How much sunlight does a flat roof receive?
Flat roofs receive less sunlight per hour than pitched roofs do overall. They don’t have as much surface area to catch the sun’s rays. They also aren’t angled to catch as much light.
The tilt angle is way different than the one of an angled roof.
The amount of sunlight a flat roof receives depends on a variety of factors including the time of year, the weather, and the size and shape of the rooftop.
The Scottish Highlands typically receive the least sunlight, while those in the south of the country receive plenty, like Kent or East Sussex.
Types of solar panels for flat roofs
- Single-axis panels
These panels are easier to install on a flat roof than traditional panels, but they’re typically less efficient at generating power.
- Tilted panels
Tilting the panels on a flat roof can increase the amount of light they receive. They’re usually more expensive and challenging to install than single-axis panels, however.
- Hybrid panels
Hybrid panels combine tilted panels with single-axis panels. They may cost less and be easier to install, but hybrid panels tend to be more efficient.
Installing solar panels on a flat roof: What to know
- Get free or low-cost installation estimates
Even though installing a solar panel on a flat roof costs less, you’ll want to make sure you’re getting a fair price. Check with solar installation companies in your area to make sure you’re receiving the best deal.
- Use a solar installer that has experience with flat roofs
You may want to consider hiring an installer that specializes in installing panels on flat roofs. They’re more likely to know the best way to do it and how to make the panels as efficient as possible.
- Consider the sun path chart
A sun path chart can tell you the hours of the day when the sun is the strongest, and when it’s shaded by buildings and trees. This can help you identify when your panels are receiving the most sunlight, which can help you keep them shaded.
Final words: Going solar doesn’t need a pitched roof!
While pitched roofs are the best option for installing a solar panel, not all properties have this type of roof.
Flat roofs are more common and can still provide you with free electricity and energy for your home.
Solar panels on a flat roof may produce less energy than those on a pitched roof. But the energy they do generate is free. Even if your roof isn’t ideal for solar panels, you can still benefit from going solar.