Roof hooks

Roof hooks for photovoltaic systems: stability and safety on the roof

Roof hooks are essential components when installing photovoltaic systems on pitched roofs. They serve as connecting elements between the substructure and the roof structure to ensure that the solar modules are securely and stably attached. Choosing the right roof hooks not only affects the longevity of the system, but also its resistance to weather influences.

Why are roof hooks so important?

Roof hooks have several important functions:

• Secure fastening: They connect the PV substructure to the roof structure without affecting the tightness of the roof.
• Load capacity: High-quality roof hooks withstand wind and snow loads and ensure long-term stability of the system.
• Flexibility: Different roof hook models enable adaptation to different roof types and inclinations.
• Material resistance: Corrosion-resistant materials such as stainless steel ensure a long service life and minimal maintenance.

Types of roof hooks

Depending on the roof type and mounting system, there are different roof hook models:

1. Standard roof hooks

   • Suitable for tiled roofs
   • Are attached under the roof tiles to accommodate the supporting profiles of the substructure
   • Flexibly adjustable for different roof pitches

2. Adjustable roof hooks

   • Ideal for uneven roof structures or different heights of the roof battens
   • Height- and laterally adjustable for optimal adjustment

3. Flat roof hooks

   • Developed for low roof pitches or special roofs with a low installation height
   • Often with additional fixation to ensure secure anchoring

4. Special roof hooks

   • Adaptable for special roof materials such as slate, corrugated iron or bitumen roofs
   • Special solutions for demanding roof structures

Materials and Load capacity

Roof hooks are usually made of:

• Stainless steel: Highly corrosion-resistant, durable and resistant to extreme weather conditions.
• Aluminium: Light, yet strong, but less resilient than stainless steel.
• Galvanized steel: Inexpensive, but more susceptible to corrosion if the protective layer is damaged.

The load capacity of roof hooks depends on factors such as the roof pitch, the wind and snow load zone and the quality of the fastening. A precise calculation by a specialist is recommended to avoid long-term damage to the roof structure.

Assembly and installation

The installation of roof hooks takes place in several steps:

1. Roof inspection: Checking the roof structure for stability and load-bearing capacity.
2. Exposing the roof battens: Removing individual roof tiles to attach the roof hook.
3. Fixing the roof hook: The roof hook is screwed to the roof batten and aligned.
4. Replacing the tiles: Adjusting the tiles to ensure a watertight seal.
5. Fastening the substructure: Connecting the roof hook to the support profiles the PV system.

Installation must be carried out carefully to avoid damage to the roof covering and thus possible leaks. In addition, roof hooks should be regularly maintained to ensure long-term safety.

Cost factors and cost-effectiveness

The cost of roof hooks varies depending on the material, quality and manufacturer. Stainless steel roof hooks are generally more expensive, but offer greater durability and resistance. The following factors also influence the total costs:

• Installation effort: Simple standard roof hooks can be installed more quickly than special solutions.
• Number of roof hooks: The amount required depends on the size of the PV system and the load calculation.
• Additional sealing: If special roof sealing is required, this can increase the costs.

Investments in high-quality roof hooks pay off in the long term because they ensure the safety and stability of the PV system and minimize the risk of damage to the roof.

Legal requirements and standards

When installing roof hooks, various standards and regulations must be observed:

• DIN EN 1991-1-4: Regulations on wind loads
• DIN EN 1991-1-3: Specifications for snow loads
• Roofing regulations: Compliance with installation guidelines to ensure roof stability

There may also be regional building regulations that must be observed. Professional installation by trained craftsmen ensures compliance with all relevant safety requirements.

Conclusion

Roof hooks are an indispensable element for the safe and stable installation of photovoltaic systems on pitched roofs. Choosing the right roof hooks influences the longevity of the system and its resistance to wind and snow loads. High-quality materials and professional installation ensure maximum safety and cost-effectiveness. Anyone who invests in durable and stable roof hooks ensures that their solar system produces reliably clean energy for many years to come.