How many solar panels can I fit on my roof?

If you’re a homeowner, you might be thinking about installing solar panels on your home. Solar panels have many benefits. A study conducted in Australia during a one-year period showed that houses with solar panels saved money on energy bills and reduced CO2 emissions. They’re a great way to save money and help the planet, and they also increase home value.

However, before you make any big decisions or purchases, you could have some questions about them, and with the amount of information you can find out there, it’s easy to get confused or lost. This article covers some of the most important questions you should have in mind before installing solar panels in your home.

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Is my roof suitable for solar panels?

You might have asked yourself this question when you first thought of installing solar panels in your home, and the good news is that most roofs are suitable for solar panels. But some might be better than others, as it is easier for professionals to install solar panels on certain types of roofs than on others.

The age of your roof also plays a role. Solar panels can last up to more than 20 years, so it is recommended that your roof is less than 15 years old, installing them on a roof that will soon be replaced doesn’t make much sense. It is also recommended that you do any necessary repairs before installing the panels.

Check out the list below to find your roof material.

How many solar panels can I fit on my roof?

All homes are different; some have more space than others. Likewise, some will need more panels than others if there is a big tree or building nearby obstructing the sunlight. Luckily, there’s a way to calculate how many panels will fit on your roof.

You’ll need to know the area of your roof. You’ll need three measurements to calculate this:

1. The height of the highest point of your roof to the joists. (A)
2. The distance from the apex horizontally at joist level until the eaves of your roof. (B)
3. The length of your roof’s apex. (C).

Step 1

Once you have the measures, you’ll need to use this formula: A² + B² = X²

X is the distance from the apex to the edge of your roof.

Step 2

After you get your result, you can use it to calculate the available roof space for your panels
using this formula:

C x X = area of roof

Step 3

Lastly, deduct 30 cm for the edge of your roof, since that area cannot be used. And if you don’t feel like climbing up to your roof, there’s an easier way to know the area of your roof. Simply go to Google’s Project Sunroof and enter your address. It will tell you the roof area available for solar panels based on 3D model of your roof.

Then, to calculate how many solar panels will fit on your roof, you’ll need to divide the area of your roof by the area of a solar panel. On average, a solar panel is 3 feet by 5 feet, which means you’ll need to divide the area of your roof by 15 to get an idea of how many panels your roof can fit.

How long do solar panels last?

Your solar panels can last for decades. On average, their life span is 25 to 30 years. This doesn’t mean they will stop working; it just means they will start to degrade and their ability to absorb sunlight will reduce, producing less energy. If after these years you see your energy bill increasing again, it could mean that it’s time to invest in new panels.

It is also important to take good care of your panels to make sure they last as long as possible and also work in the best way possible. This includes cleaning them as advised before, and checking for debris weekly, as it can sometimes break the panels.

How often should solar panels be cleaned?

Another good thing about solar panels is that they require low maintenance, but keeping them clean is important. Like most things, they will work better and be more efficient if they’re kept clean. How often you should clean them depends mostly on your environment. If you live in an area where it doesn’t rain much, you’ll need to clean them more often than if you live in an area with heavy rain, as rain tends to clean them.

It’s advised to clean them at least once every six months, and you should call a professional when it’s time to do so. You should also check for debris every week, and if there is any, remove it gently.

Written by Billy Guteng. September 10, 2023

Billy was born in France, and has lived in multiple cities around the world ever since. He loves art, design and architecture and he supports the KUKUN team as a content provider.