Can Your Roof Support a Photovoltaic Installation?

Installing a photovoltaic system on rooftops is a major decision that combines energy efficiency with sustainability. However, before taking this step, it is essential to ensure that the structure can withstand the additional loads without compromising its integrity.

Below, we present a practical guide to verify the load-bearing capacity of roofs.

Identifying the Type of Roof

The first step is to determine whether the roof is flat or pitched, as well as to identify the structural material being used: concrete, steel, wood, among others. This initial classification will help guide the calculations and preventive measures.

Having this clear will also allow you to start thinking about the materials required for your installation—especially the requirements you’ll face when choosing a structure.

Review of Structural Plans

It is essential to have the original building, house, or warehouse plans. These contain the design specifications and load limits. The following must be checked:

Admissible loads: dead load, live load, and environmental loads (snow and wind).
Load-bearing elements: beams, columns, and slabs.

Calculation and Comparison

The next step is to determine the total load the structure will bear. You will calculate:

Self-weight of the system. For example, solar panels (10–12 kg/m²), support structures, and—if using non-penetrating systems—ballasts.

This is why supports are always designed to be as lightweight as possible, using materials such as aluminum, which is both strong and lightweight. This is one of the advantages of working with a manufacturer of flexible solutions for each scenario.

Additional loads: wind, snow (if applicable), and potential loads during maintenance. This allows for future-proofing.

Finally, the total calculated value must be compared with the remaining live load capacity of the roof. In addition, safety factors established by local or international standards such as Eurocode, ASCE 7, or the Spanish Technical Building Code (CTE) must be applied.

Technical Structural Evaluation

With this data, it is advisable to carry out a complete structural analysis, including stress calculations and even simulations. The outcome should be a technical report indicating the project’s feasibility, along with recommendations and limitations.

Ideally, for large projects, you should have the support of an expert team who can assist with the analysis and determine which structure will be most suitable for the specific roof.