English 
Spanish 
5 min read
0 comments
Can solar panels damage your roof? Check out all your questions about the weight of the equipment and do not install a solar energy system without consulting a specialized professional.
The popularity of solar panels continues to grow, but many questions still surround this type of technology. One of the main concerns is the weight of a solar PV system and the ability of a roof to safely support it.. These issues gained even more prominence after the incident at the Sanctuary of Our Lady of Conception, in Recifand, Pernambuco. In this article, we will clarify everything you need to know to ensure a safe installation and understand whether solar panels can actually compromise the structure of your roof.
Can solar panels collapse your roof?
The tragic accident resulted in two fatalities and 22 people being injured when the roof collapsed, a week after the installation of a solar panel system. There is no confirmation that the presence of the solar panels contributed to the cause of the accident.
This is being verified by a team of experts in Pernambuco and as soon as the work has been completed the result will be released. Some facts about this accident is that the company that did the installation had a structural report that authorized the installation on site.
- Producing 1.000 tons of solar glass per day, Bahia is becoming the epicenter of the sector's production in Latin America with an investment of almost R$ 1 BILLION, generating thousands of jobs and boosting the country's economy and energy transition!
- Find out what the red flag is in energy and why it directly impacts the value of your electricity bill
- Find out if an Energy Storage System is a Worthwhile Investment!
- Energy Transformation: Driving Mineral Projects in Brazil and Connecting Executives in São Paulo
By analyzing the photo of the installed solar panel system and manually counting the existing modules, we can arrive at a total of approximately 120 photovoltaic modules.
Noting that, currently, the modules used in this type of installation vary between 550 w and 570 w in most companies, we use below as a reference a 550 w photovoltaic solar energy module, which is the most used module in commercial installations.
How to calculate the weight of a solar panel system?
Solar panels of this type have a unit weight of more or less 27,5 kg, depending on the manufacturer. In this way, 120 plates multiplied by the weight of 27,5 kg, per module, we would have a weight of 3.300 kg, that is, 3.3 tons of just photovoltaic modules.
Noting that to install these modules we have aluminum rails and that the weight of this structure can vary between 10 to 20% of the weight of the solar panels and the material.
Something around 10% if it is fiberglass, 20% if it is aluminum, then we would add the weight of the structure used to fix the panel, which is around 660 kg, which would give something around 3.960 kg, that is, almost 4 tons of solar panels and fixing structure.
We also did not take into account some cables connecting the modules to the inverters or microinverters. Another weight issue to know if solar panels can collapse your roof is the type of installation and if the solar energy installation is done with microinverters and if these microinverters are underneath the solar energy panel, then there would be an additional weight increase.
This component has the capacity to connect four photovoltaic modules, so for an installation of 120 solar panels, we would need 30 microinverters and the weight of a microinverter generally used in these installations is around 3,5 kg, which would be an increase of 105 kg, giving a total of 4.065 kg.
How do I know if I can install a solar energy system?
If the installation was done with String inverter, which is large and receives the connection from the panels below, that is, once inside the commercial establishment, this weight of 105 kg would be removed.
However, it would still be almost 4 tons, the weight of four popular cars on a roof. This is more or less an estimated weight based on the photo, the number of modules and the type of installation.
However, the question remains: how to calculate the weight supported by the roof that will receive this installation and whether solar panels can collapse your roof. To answer these questions, companies that install photovoltaic solar energy systems generally carry out a study and pay for a technical report to perform an analysis when it is a large-scale installation or they require the contractor to have this report.
Can solar panels collapse your roof?
The question is legitimate, and understanding the weight of a solar system is essential to ensuring a safe installation. A standard photovoltaic solar panel weighs, on average, 18 to 25 kg, and considering that a complete system can contain between 10 to 20 panels, the total weight of the system can vary from 180 kg to 500 kg, depending on the size and capacity of the project.
The weight of the fixing brackets and other components must be taken into account. To ensure the safety of the installation, it is crucial that the roof can support this additional weight without compromising its structure.
A typical roof on a brick house with a wooden frame can usually support between 15 and 20 kg per square meter. If your solar system covers an area of 20 square meters, for example, and each square meter of solar panel weighs about 10 kg, the total weight would be around 200 kg, which would be safe for most conventional roofs.
However, it is essential to carry out a technical assessment before installation to ensure that the roof is in good condition and can support both the weight of the panels and other variables, such as wind and rain.
Remember, an inspection by a civil engineer or a solar energy specialist can ensure the safety and efficiency of the installation, avoiding unpleasant surprises in the future. This care is essential to avoid damage to the structure of your home and ensure that the system works perfectly.
