Flexible installation for optimum yields on flat roofs
Reliable fastening systems – guaranteed watertight roofs
All S:FLEX flat roof mounting systems can be installed without roof penetration and are available as aerodynamic/low-ballast systems, as ballasted frames or with concrete foundation.
Our aerodynamic LEICHTmount systems require only minimal additional ballast and are the ideal solution for quick installation and for roofs with low pressure/load-bearing capacities.
Our ballasted system based on the S:FLEX Delta triangle allows installation with higher ballast quantities if necessary.
Our Delta Concrete system is the solution of choice for installations on flat concrete roofs with parapet walls.
And for quick and easy PV mounting on green roofs we offer the S:FLEX GreenLight system.
Aerodynamic flat-roof frames for east/west and south orientation
S:FLEX LEICHTmount RAIL 2.1 with extremely low surface load
The main advantages of the LEICHTmount RAIL 2.1 S/EW:
- System with General Technical Approval
- Extremely low surface load and system installation without roof penetration possible
- Low ballast due to systematic aerodynamic optimisation of the design
- Foot plates attached with a click to the ground rails to protect the roof skin from plasticizer migration
- Better pressure load distribution by increasing the number of foot plates
- Independently tested for wind safety in accordance with German and US standards
- Optimised rear ventilation for maximum energy yield
- Optimised cable management with conduit covers and edge clips
- Integrated cable ducts and covers that make cable routing possible even after system installation without additional expense or effort
- Integrated fall protection (optional)
- Roof drainage is ensured
- Capable of carrying lightning currents in accordance with DIN EN 62561 (VDE 185-561-1):2013-02
- We will gladly create the structural design for our customer's projects if required – the documentation we provide includes the structural analysis and the ballast plan
LEICHTmount RAIL 2.1 S for south orientation
Components
LEICHTmount RAIL 2.1 S ground rail
Our ground rail with attached foot plates ensures even load distribution over the roof.
LEICHTmount RAIL 2.1 base
The base serves as a lower receptacle for modules and module clamps.
LEICHTmount RAIL 2.1 tower
The tower is clicked on the floor rail and serves as an upper receptacle for modules and module clamps
LEICHTmount RAIL 2.1 foot plate
Foot plates attached with a click to the ground rails to protect the roof skin from plasticizer migration.
End and mid clamps
S:FLEX module clamps have an extremely wide clamping area and are therefore suitable for all standard modules and frame heights of 30-50 mm. High torsion resistance and our latest, ultra-smooth one-click technology make installation a snap.
Data
Application |
Flat roofs – roof pitch in general up to 5°; roof pitch > 5° up to 10° has to be checked specifically per project |
Roofing type |
Foil, bitumen, gravel, greenery, concrete |
Orientation |
South |
Module pitch |
10° / 15° |
Module size (L x W) |
1614 – 2340 mm x 985 – 1300 mm |
System surface load |
From 7.5 kg/m², incl. module & ballast |
Building height |
Max. 25 m (taller buildings up to 50 m on request) |
Distance to edges |
Installation in the roof edge and corner regions is possible |
Wind load |
Up to 2.4 kN/m² |
Snow load |
Up to 5.4 kN/m² |
System size |
Max. area size 20 x 20 m |
Downloads
A data sheet with technical information about our LEICHTmount RAIL systems is available for download here:
S:FLEX LEICHTmount RAIL 2.1 S/EW
For assembly instructions, please click here:
S:FLEX assembly instructions LEICHTmount RAIL 2.1 S
Planning
If you would like to take advantage of our planning support, you can:
– use our planning aid
– fill out our online form
– send an e-mail to
– or call us: +49 (0)761 888 56 08 0
LEICHTmount RAIL 2.1 EW for east/west orientation
Components
LEICHTmount RAIL 2.1 EW ground rail
Our ground rail with attached foot plates ensures even load distribution over the roof.
LEICHTmount RAIL 2.1 base
The base serves as a lower receptacle for modules and module clamps.
LEICHTmount RAIL 2.1 tower
The tower is clicked on the floor rail and serves as an upper receptacle for modules and module clamps
LEICHTmount RAIL 2.1 foot plate
Foot plates attached with a click to the ground rails to protect the roof skin from plasticizer migration.
End and mid clamps
S:FLEX module clamps have an extremely wide clamping area and are therefore suitable for all standard modules and frame heights of 30-50 mm. High torsion resistance and our latest, ultra-smooth one-click technology make installation a snap.
Data
Application |
Flat roofs – roof pitch in general up to 5°; roof pitch > 5° up to 10° has to be checked specifically per project |
Roofing type |
Foil, bitumen, gravel, greenery, sheet concrete |
Orientation |
East/west |
Module pitch |
10° / 15° |
Module size (L x W) |
1550 – 2400 mm x 985 – 1300 mm (EW 10°) 1550 – 2400 mm x 985 – 1080 mm (EW 15°) |
System surface load |
From 9.5 kg/m², incl. module & ballast |
Building height |
Max. 25 m (taller buildings up to 50 m on request) |
Distance to edges |
Installation in the roof edge and corner regions is possible |
Wind load |
Up to 2.4 kN/m² |
Snow load |
Up to 5.4 kN/m² |
System size |
Max. area size 20 x 20 m |
Downloads
You can download a data sheet with technical information about our LEICHTmount RAIL systems here:
S:FLEX LEICHTmount RAIL 2.1 S/EW
The assembly instructions are also available for download:
S:FLEX assembly instructions LEICHTmount RAIL 2.1 EW
Planning
If you would like to take advantage of our planning support, you can:
– use our planning aid
– fill out our online form
– send an e-mail to
– or call us: +49 (0)761 888 56 08 0
The lightweight alternative
Aerodynamic, lightweight and totally wind-safe installation possible without roof penetration. The S:FLEX LEICHTmount RAIL 2.1 mounting system for framed PV modules is the ideal solution for flat roofs – even with a low load-bearing capacity.
Both variants – the System S for the traditional south-facing orientation and the EW variant for maximum east/west coverage – deliver outstanding economy. The use of only a few, pre-assembled components, most of which can be connected easily and securely with one click, makes installation easy, efficient and fast. No need for time-consuming measuring, drilling or cutting on the roof.
In addition to the wide new foot plates clicked onto the substructure, the tool-free installation without self-drilling screws or sharp-edged components provides additional protection – even for the most delicate roof membrane.
The S:FLEX LEICHTmount CF for south orientation (S) or east/west coverage (EW)
The main advantages of the LEICHTmount CF S/EW:
- Patented, statically optimised systems
- Wind-tunnel tested to the latest standards at up to 250 km/h
- S variant with tilt angle of 5°, 10° or 15° and optimised row spacing for an 18° or 25° shading calculation area available
- Fast and easy installation
- Lower transport costs due to minimal use of materials
- Includes fleece pads proven via durability tests
- Certified module clamps with earthing pins that provide system earthing in accordance with international standards
- Problem-free water drainage and optimal module back-ventilation
- Optimised wind suction openings for reduced ballast
- Also suitable for roof-edge zones
- Also available as a heavy duty, easy-to-install Alpine version
- Certified to UL 2703, fire tested to UL 1703, tensile and load tested to IEC 61215
- We will gladly create the structural design for our customer's projects if required – the documentation we provide includes the structural analysis and the ballast plan
LEICHTmount CF S for south orientation
Components
LEICHTmount CF S supports
These supports consist of optimised materials and are supplied with a 5°/10°/15° tilt angle. Our rail-less support system offers flexible mounting options, even for uneven roofs or near interfering elements.
LEICHTmount CF S ballast tray
The use of our ballast trays enables uniform distribution of the ballast and prevents the formation of concentrated loads. Particularly suitable for use in areas with high wind loads.
LEICHTmount CF S module clamps
Height-adjustable module and end clamps for all frame heights from 30–46 mm. Install the clamps directly on the supports with standard earthing pins.
Data
Application |
Flat roofs – roof pitch up to 4° |
Orientation |
South |
Module pitch |
5° / 10° / 15° |
Shading calculation area |
Module pitch 5° : 18° / Module pitch 10° and 15° : 18° or 25° |
Module size |
All common module sizes with frame heights from 30–46 mm |
Surface load |
Approx. 10 kg/m² of covered roof surface |
Building height |
Max. 25 m |
Distance to edges |
Installation in the roof edge and corner regions is possible |
Wind load |
Suction load up to 2.4 kN/m² |
Snow load |
Standard version, up to bis 2.4 kN/m² / Alpine version up to 4.4 kN/m² |
System size |
The maximum module array size is 120 modules (12 modules per row and 10 consecutive rows) |
Downloads
Assembly instructions can be downloaded here:
S:FLEX assembly instructions for LEICHTmount CF S
For the data sheet please click here:
S:FLEX data sheet LEICHTmount CF S/EW
Planning
Information about our Planning Tool is available HERE.
If you would like to take advantage of our planning support, you can:
– fill out our online form
– send an e-mail to
– or call us: +49 (0)761 888 56 08 0
LEICHTmount CF EW for east/west orientation
Components
LEICHTmount CF EW supports
These supports consist of optimised materials and are supplied with a 10° tilt angle. Our rail-less support system offers flexible mounting options, even for uneven roofs or near interfering elements.
LEICHTmount CF EW ballast tray
The use of our ballast trays enables uniform distribution of the ballast and prevents the formation of concentrated loads. Particularly suitable for use in areas with high wind loads.
LEICHTmount CF EW module clamps
Height-adjustable module and end clamps for all frame heights from 30–46 mm. Install the clamps directly on the supports with standard earthing pins.
Data
Application |
Flat roofs – roof pitch up to 4° |
Orientation |
East/west |
Module pitch |
10° |
Shading calculation area |
18° |
Module size |
All common module sizes with frame heights from 30–46 mm |
Surface load |
Approx. 15 kg/m² of covered roof surface |
Building height |
Max. 25 m |
Distance to edges |
Installation in the roof edge and corner regions is possible |
Wind load |
Up to 2.4 kN/m² |
Snow load |
Standard version, up to bis 2.4 kN/m² / Alpine version up to 4.4 kN/m² |
System size |
Variable arrangement as per the project report – the maximum module array size is 192 modules (12x2 modules per row and 8 consecutive rows) |
Downloads
Assembly instructions can be downloaded here:
S:FLEX assembly instructions for LEICHTmount CF EW
For the data sheet please click here:
S:FLEX data sheet LEICHTmount CF S/EW
Planning
Information about our Planning Tool is available HERE.
If you would like to take advantage of our planning support, you can:
– fill out our online form
– send an e-mail to
– or call us: +49 (0)761 888 56 08 0
The aerodynamic alternative
On flat roofs where roof penetration is not possible or desired but the roof construction and load-bearing capacities do not permit ballasting, an aerodynamic, largely ballast-free solution is a viable alternative.
Installed quickly and removable without a trace – yet as stable, storm-proof and durable as ballasted mounting systems or those that are firmly connected to the roof membrane – our aerodynamically designed frames are based on a well-thought, pioneering concept. In particular, our LEICHTmount systems, which can be installed in both south-facing and east-west orientations, come highly recommended as innovative and uncomplicated flat-roof installations.
S:FLEX mounting system for concrete roofs
S:FLEX Delta Concrete raised flat-roof mounting systems, perfect for roofs with parapet walls
The advantages of the S:FLEX Delta Concrete:
- The Delta Concrete is designed to be used on flat
concrete roofs and offers the possibility to build over obstacles in order to optimise performance per area - Lightweight, material-efficient design makes the
Delta Concrete a modular and flexible system with few components - Almost all framed and frameless module types with common dimensions – especially bifacial modules – can be installed either in landscape or portrait mode
- Excellent rear ventilation ensures high yields and makes the system suitable for hot regions.
- Long service life, complete recyclability and corrosion resistance with a 10-year warranty
- System load capacity in accordance with DIN EN 1991-1-4:2010-12 (wind loads) and DIN EN 1991-1-3:2010-12 (snow loads), on request testable structural calculations for maximum safety
- We will gladly create the structural design for our customer's projects if required – the documentation we provide includes the structural analysis as well as the installation plan
Components
Base rail Delta Concrete
Lightweight, structurally optimised hollow chamber rails in various lengths.
Pillar Delta Concrete
Sturdy aluminium posts available in various lengths for different inclinations and clearance.
Base Delta Concrete
Robust support for screw fastening of the mounting system to the concrete foundation.
Top Delta Concrete
Gusset plate mounted at the top of the pillar to attach the base rail.
End and mid clamps Hawk HK
Module clamps with a wide clamping area and one-click technology for smooth module installation. Optionally available with grounding kit. UL 2703 certification pending.
Data
Application |
Flat roofs and ground-mounted |
Foundation |
Concrete, screw fastening |
Module type |
Framed modules, also frameless (with additional horizontal rail) and bifacial modules |
Module orientation |
Horizontal/vertical |
Inclination |
Up to 20% |
Terrain slope |
N-S: any E-W: module area 1° / terrain 10° |
Max. module field size |
12 x 4 modules in landscape format 12 x 3 modules in portrait format |
Max. loads |
5.4 kN/m² |
Downloads
You can download a data sheet with technical specifications of our flat-roof frame Delta Concrete here:
S:FLEX Delta Concrete data sheet
Assembly instructions are available here:
S:FLEX Delta Concrete assembly instructions
Planning
If you would like to take advantage of our planning support, you can:
– fill out our online form
– send an e-mail to
– or call us: +49 (0)761 888 56 08 0
The S:FLEX Delta Concrete flat roof structure is a modular and flexible system with a lightweight, material-efficient design and few components that can be quickly planned and installed. No drilling of aluminum or steel is necessary on site. Power optimisers and (micro-)inverters can be easily attached to the structure.
S:FLEX flat roof system with ballast
Raised flat-roof frames with the S:FLEX Delta triangle
All benefits of our systems with the S:FLEX Delta triangle at a glance:
- Variable use of framed and frameless PV modules on flat roofs of old and new buildings
- Installation on ballast stones, hanger bolts or trapezoidal sheet metal rails is possible; special solutions on request
- Horizontal or vertical module installation
- Delta triangles are available with tilt angles from 5° to 45° (in 5° increments)
- Minimised storage and transport costs: The triangles are delivered pre-installed but collapsed. Transport and storage of up to 252 pcs. per 130x80 cm (approx.) pallet
- Quick installation of the substructure thanks to a very high degree of pre-assembly, our latest one-click technology and a detailed installation recommendation
- Maximum flexibility during installation due to variably adjustable module clamps and end clamps for modules with a frame height of 30–50 mm; certified laminate clamps are available for frameless modules
- Excellent adaptability to ensure a flat PV array – even on uneven roof surfaces thanks to height-adjustable mounting rails
- Long service life, complete recyclability and corrosion resistance thanks to 100% aluminium and stainless steel components with a 10-year warranty
- System load capacity in accordance with DIN EN 1991-1-4:2010-12 (wind loads) and DIN EN 1991-1-3:2010-12 (snow loads), on request testable structural calculations for maximum safety
- We will gladly create the structural design for our customer's projects if required – the documentation we provide includes the structural analysis and the ballast plan
Components
S:FLEX Delta triangle
Our base triangles for flat-roof elevation are pre-assembled for quick installation.
Mounting rails
S:FLEX mounting rails are used as floor rails to mount the base triangles or as module carrier rails for vertical mounting. The hollow chamber rails are structurally optimised and available in different cross-sections and lengths.
Rail connectors
To ensure structurally identical properties in the area of the rails and the connections.
Trapezoidal sheet metal rails
Our trapezoidal sheet metal rails allow direct installation on trapezoidal sheet metal roofing. In addition, they can be used as floor rails to support high quantities of ballast.
End and mid clamps
S:FLEX module clamps have an extremely wide clamping area and are therefore suitable for all standard modules and frame heights of 30-50 mm. High torsion resistance and our latest, ultra-smooth one-click technology make installation a snap.
Data
Application |
Flat roof |
Pitch |
Available in 5° increments from 5° to 45°; other angles upon request |
Module type |
Framed and frameless modules |
Module size |
Horizontal installation: Module width 1175 mm max. Vertical installation: Module length 2185 mm max. (Other module sizes upon request) |
Module orientation |
Vertical/horizontal |
Wind load |
Up to 2.4 kN/m² |
Snow load |
Up to 2.4 kN/m² |
Advantages |
Freely selectable position and size of the module array / ideal even for small systems with 1, 2, 4 or 8 modules / low transport and storage costs due to delivery of collapsed triangles |
Note |
The load-bearing capacity of the roof must be checked in advance |
Downloads
You can download a data sheet with detailed technical specifications of our flat-roof frame with the Delta triangle here:
S:FLEX Delta triangle
Planning
If you would like to take advantage of our planning support, you can:
– use our planning aid
– fill out our online form
– send an e-mail to
– or call us: +49 (0)761 888 56 08 0
The easiest way to use flat roofs for photovoltaic systems
The S:FLEX roof frame with ballast is the simple and proven solution for non-penetrative, green-roof-compatible flat-roof installations. A number of attachment and ballast options are available depending on the planned system and the conditions on site.
On flat roofs without roof structures and in regions with high wind loads, we recommend installing Delta triangles for ballasting. In this case, a particularly high quantity of ballast can be flexibly distributed over the rails.
For roofs with a lower load-bearing capacity and roof superstructures on which longer rails cannot easily be laid, the triangles are attached directly to ballast blocks/stone slabs.
Installation of the substructure with S:FLEX Delta triangles with our universal one-click installation principle and ballast – such as weighting stones, gravel or green-roof granules – ensures absolute roof-tightness and easy dismantling. It also offers all the benefits of a raised-panel solution. As well as straightforward maintenance and easy accessibility of both the roof surface and the PV system, high system efficiencies are also achieved thanks to optimal rear ventilation.
The solution for green roofs producing solar energy
Quick PV installation on green roofs with S:FLEX GreenLight
The advantages of the S:FLEX GreenLight System at a glance:
- Particularly easy and quick to install solution for green roofs
- Water storage volume of 39.5 l for high water retention
- Modules can be mounted vertically and horizontally
- South and east-west orientation (saddle roof and butterfly assembly possible)
- Available for 3 different inclination angles: 10°, 15° and 20°
- High module distance from the ground for simplified maintenance of the green roof and optimised yields
- Optional: non-penetrative fall arrest or restraint system
- Static calculations according to Eurocode and regional standards
Components
GreenLight base plate
Drainage tray with high water storage volume (39.5 l) made in Germany from recycled HDPE.
GreenLight ST universal profile
A rail for mounting framed photovoltaic modules in all common sizes.
GreenLight Knickfix angle bracket 10°/15°/20°
Triangular connection between base plate and mounting rail, available for three different module inclination angles.
End and mid clamps
S:FLEX module clamps have an extremely wide clamping area and are therefore suitable for all standard modules and frame heights of 30-50 mm. High torsion resistance and our latest, ultra-smooth one-click technology make installation a snap.
Data
Application |
Green roof (extensive) |
Fastening |
Without roof penetration / ballasted |
Options |
South or East-West-Orientation |
Module pitch |
10°, 15°, 20° |
Module type |
Framed modules |
Module orientation |
Vertical/horizontal |
Roof pitch |
5° max. |
System size |
2 modules min. |
Advantages |
no roof penetration / high water storage volume / extremely quick installation / suitable for all common module sizes / optional integration of fall protection |
Downloads
A data sheet with more information on our green roof solution:
S:FLEX GreenLight
For assembly instructions, please click here:
S:FLEX GreenLight assembly instructions
Planning
If you would like to take advantage of our planning support, you can:
– fill out our online form
– send an e-mail to
– or call us: +49 (0)761 888 56 08 0
Especially for the combination of photovoltaics and green roofs
The S:FLEX GreenLight System with substrate ballasting and integrated water reservoir is the quick and easy solution for penetration-free extensive green roofs. The large distance between the modules and the substrate surface prevents heat accumulation and avoids yield losses due to the plants shading the PV modules. For optimal use of roof space as well as easy care, inspection and maintenance, we recommend the butterfly assembly variant with its raised structure between the rows. If required and desired, the problem-free integration of a fall protection is possible.