S4 Mounting System: the mounting systems manufacturer focusing on robust, universal and future-proof in-roof systems.
31 Mar 26
As the solar industry has matured, in-roof photovoltaic (BIPV) systems have become increasingly popular for residential and new-build projects. However, early generations of roof-integrated solar systems revealed several structural and practical challenges.
Installers and developers often encountered issues relating to installation complexity, long-term watertightness, maintenance access, and reliance on proprietary components that could limit compatibility with different solar panels.
S4 Mounting Systems was founded to address these challenges.
By building on lessons learned from earlier in-roof solar technologies, S4 has developed a second-generation mounting solution focused on structural reliability, simplified installation, and long-term system compatibility.
A key element of the S4 design philosophy is its waterproofing strategy. Unlike some early systems that relied on the photovoltaic module itself to maintain roof integrity, S4 RooFit separates the weatherproofing function from the solar panel. This approach ensures that the building remains protected even during panel maintenance, replacement, or in the event of module failure.
This experience-led engineering philosophy highlights the S4 system and supports its suitability for large-scale residential deployment, new-build developments, and long-term solar integration.
S4 RooFit - The Universal In-Roof Mounting System:
Designed around the universal patented base plate, S4 RooFit is a system that combines architectural integration, structural performance and long-term sustainability. It’s a fully engineered, certified and scalable solution for residential and new-build projects.
Key features:
- Temperature tolerance: -20°c to 85°c
- Suitable for roof pitches from 12° – 70°
- Universal system compatibility, supporting a wide range of solar panels
- Flexible panel layouts supporting portrait or landscape configuration
- Integrated waterproofing design
- Reinforced rear structure to deliver resistance to pressure loads, wind uplift, long-term structural stress
- Long-term compatibility: one system for all panel sizes, not linked to panel lifecycle
- 5 component system – allowing easy installation and reduced installation risk
One of the defining principles of the S4 system is its universal compatibility.
The mounting platform has been designed to support photovoltaic panels from a wide range of manufacturers, allowing the system to adapt as the solar market evolves.
- Faster, repeatable installations
- A consistent system across multiple projects
- Long-term system compatibility
- Reliable compliance with building standards
These industry insights have helped shape the evolution of modern in-roof photovoltaic design standards across Europe.
Materials:
Durability is central to the engineering philosophy of S4 Mounting Systems. Each component is manufactured using materials selected to perform reliably under long-term outdoor conditions while complying with UK product safety and environmental regulations.
Key materials include:
EPDM Rubber Seals (70 Shore A)
High-performance EPDM rubber maintains optimal compression under clamping pressure, helping ensure reliable weather sealing while resisting deformation over time.
Recycled Polymer Compounds
Polymer materials containing recycled content sourced from the automotive industry contribute to the system’s sustainability while maintaining strong mechanical properties.
High-Grade Aluminium and Stainless Steel
Structural components are manufactured using corrosion-resistant metals designed to withstand harsh weather conditions and long-term environmental exposure.
S4 also supports circular economy principles, with system materials designed to be recyclable at the end of their service life.
Certifications:
S4 mounting systems have been developed and tested to meet recognised industry standards and certification requirements. Relevant certifications include:
- MCS Certification
- BBA Certification
- IEC 61215
- IEC 61730
The system has also undergone fire testing and is compatible with REC and Eurener panels.
The S4 Mounting System Platform:
The S4 Configurator is a platform designed to assist in designing, validating, and deploying the photovoltaic systems with compliance, technical and regulatory frameworks in mind.
Developed in accordance with:
- European Eurocodes and national annexes
- Relevant British Standards (BS)
- MCS 012 requirements
- NHBC expectations for new-build housing
Extensive Module Database with a library of over 2,000 solar panels:
- Dimensions and tolerances of each solar panel
- Frame geometry
- Fixing interface characteristics
- Manufacturer specific constraints
Real-world installation conditions:
- Portrait and landscape layouts
- Variable roof geometries and pitches
- Different fixing strategies and overlap zones
- Compatibility with rood coverings and drainage principles
S4 Mounting System RooFit
Designed around the universal patented base plate, S4 RooFit is a system that combines architectural integration, structural performance...
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