Choosing the right solar roof mounting structures is one of the most important factors in ensuring the safety, durability, and profitability of a rooftop photovoltaic system. However, many decisions are still made solely based on the structure’s price or speed of installation, neglecting critical aspects such as roof compatibility, wind loads, and the building’s load-bearing capacity.
In Spain, where climatic conditions, construction types and regulations vary significantly depending on the location, correctly selecting the support structure can make the difference between an efficient installation for more than 25 years or a constant source of incidents and maintenance costs.
In this guide we analyze how to choose the best solar roof structures for industrial buildings , factories and commercial buildings , taking into account technical, structural and safety criteria.
Why is the structure so important in a photovoltaic installation?
Cuando se habla de una planta fotovoltaica, la atención suele centrarse en los módulos y los inversores. Sin embargo, la estructura es el elemento que:
- It transmits all loads to the building.
- It guarantees stability against the wind.
- Mantiene la inclinación y orientación óptimas.
- It prevents leaks and damage to the roof.
- Determina la vida útil de la instalación.
A poorly designed structure can cause:
- Deformations in the roof.
- Pérdidas de producción por movimientos o sombras.
- Water leaks.
- Premature corrosion.
- Risks to the safety of workers and users.
For this reason, the choice must always be made through a specific analysis of the building and the site conditions.
Step 1: Identify the roof type
Before selecting any system, it is essential to know the type of roofing that exists.
Corrugated metal roof
It is one of the most common in industrial buildings.
Advantages
-
- Reduced weight.
- Easy installation.
- Good capacity for mechanical fixings.
Considerations
-
- Check sheet metal thicknesses.
- Analyze the condition of the roof.
- Check the strength of the belts and the main structure.
The most commonly used solutions are coplanar systems or structures with reduced inclination.
Sandwich-type Roof
Very common in modern logistics and industrial buildings.
Advantages
-
- Excellent thermal insulation.
- Quick installation.
Critical aspects
-
- Avoid panel compression.
- Use specific fixings.
- Ensure watertightness.
The quality of the fixing system is crucial to prevent future leaks.
Fiber cement roofing
Still present in many old industrial facilities.
Risks
-
- High fragility.
- Possible presence of asbestos.
- Regulatory restrictions for its handling.
In these cases, it is essential to carry out a specific evaluation before planning the installation of panels on roofs.
Flat roofs
Common in commercial buildings and logistics centers.
Possibilities
-
- Ballasted systems.
- Mechanically fixed systems.
- East-west configurations.
- Southern configurations.
The choice will depend primarily on the allowable loads and wind actions.
Installation on sandwich panels using Gulpiyuri 75 in sections. Discover Gulpiyuri 75 here.
Step 2: Verify the structural capacity of the vessel
One of the most common mistakes is assuming that a roof can support any photovoltaic installation.
Before selecting a structure, it is necessary to analyze:
- Existing permanent loads.
- Overuse.
- Snow loads.
- Wind loads.
- State of conservation of the ship.
Learn more about sizing solar structures on industrial roofs here.
Key questions
How old is the ship?
Older structures may have suffered degradation or corrosion.
¿Se dispone del proyecto original?
Structural documentation allows for the verification of load-bearing capacities and the optimization of the design.
Are there any previous expansions or modifications?
Previous interventions may alter the structural behavior initially intended.
The panels fly off because not all the data about the initial state of the roof is known.
Step 3: Analyze wind loads
In much of Spain, wind is the dominant factor in the design of rooftop photovoltaic systems.
The loads vary according to:
- Geographic location.
- Altitude.
- Urban or rural environment.
- Building height.
- Roof geometry.
Why is it so important?
The wind can generate:
- Suction on modules.
- Removal of fixings.
- Displacements of ballasted structures.
- Fatiga en elementos de unión.
Por ello, las mejores estructuras de cubierta solares incorporan:
- Estudios aerodinámicos.
- Calculations according to Spanish regulations.
- Optimization of fixings.
- Distribución eficiente de cargas.
Discover how wind loads affect a photovoltaic installation here.
Step 4: Choose between coplanar or inclined systems
Coplanar systems
The modules follow the existing slope of the roof.
Advantages
-
- Less visual impact.
- Less exposure to wind.
- Less additional weight.
Recommended for
-
- Sloping roofs.
- Industrial buildings.
- Factories with structural limitations.
Installation on corrugated metal sheeting with Gulpiyuri 30 sections. 2.8 MW. Discover Gulpiyuri 30 here
Inclined systems
Permiten modificar el ángulo del módulo.
Advantages
-
- Energy optimization.
- Greater design flexibility.
Disadvantages
-
- Increased wind loads.
- Greater structural complexity.
They are common on flat roofs and in large commercial facilities.
Installation at Pecomark with the Picos Sur System. Discover ballasted systems here.
Step 5: Evaluate the materials of the structure
Durability depends largely on the material used.
Structural aluminum
Advantages
-
- Light.
- Corrosion resistant.
- Easy handling.
Ideal para reducir cargas sobre cubiertas ligeras.
Acero Magnelis®
Increasingly used by leading suppliers of solar structures.
Benefits
-
- Excellent corrosion resistance.
- High durability in harsh environments.
- Menor mantenimiento.
Especialmente recomendable para:
-
- Coastal areas.
- Industrial environments.
- Long-life installations.
Galvanized steel
It continues to be a widely used solution.
Its suitability will depend on the thickness of the galvanizing and the environmental conditions.
Step 6: Design with future maintenance in mind
A photovoltaic installation does not end when it is connected to the grid.
For more than 25 years it will be necessary to do the following:
- Cleaning services.
- Inspections.
- Electrical inspections.
- Sustituciones de componentes.
Therefore, the design must consider from the outset:
- Secure access.
- Technical walkways.
- Lifelines.
- Maintenance areas.
The integration between solar roof structures and security systems is becoming increasingly relevant in industrial projects.
Step 7: Comply with Spanish regulations
All installations must comply with:
Technical Building Code (CTE)
Especially with regard to:
-
- Structural safety.
- Wind actions.
- Snow actions.
Eurocódigos estructurales
Used as a reference for structural calculations.
Discover wind zones according to CTE and Eurocode here.
Regulations for the prevention of occupational risks
Essential during:
-
- Instalation.
- Maintenance.
- Operation.
A correctly calculated structure must always be accompanied by the corresponding supporting documentation.
Common mistakes when selecting solar roof structures
Choose based solely on price.
The cost of the structure usually represents a small part of the total investment, but it has a huge impact on safety and durability.
Do not check the load-bearing capacity of the cover
It can cause serious structural pathologies.
Ignorar las cargas de viento
One of the most common mistakes in poorly designed projects.
Use generic systems
Each roof requires a specific solution.
No planificar el mantenimiento
It complicates future interventions and increases operating costs.
Discover the 7 most common mistakes here
How to choose a solar structure supplier
Not all suppliers offer the same level of engineering.
Before deciding, it is advisable to consider:
- Experience in industrial projects.
- Capacidad de cálculo estructural.
- Documentación técnica disponible.
- Material certifications.
- Support during the design process.
- On-site assistance.
Un buen proveedor no vende únicamente una estructura; aporta soluciones adaptadas al edificio, al emplazamiento y a los requisitos de producción energética.
Alusín Solar, your supplier of solar structures
The choice of solar roof structures is a strategic decision that directly affects the safety, production and lifespan of any photovoltaic installation on industrial buildings , factories and commercial buildings .
Analizar la tipología de cubierta, verificar las cargas estructurales, estudiar las acciones de viento y seleccionar materiales adecuados son pasos imprescindibles para garantizar un proyecto exitoso.
In a market where solar panel systems continue to grow in both self-consumption and large-scale installations and photovoltaic parks , supporting engineering is playing an increasingly important role. Choosing solutions specifically designed for each roof is the best guarantee of long-term performance, safety, and profitability.
