Flat roof mounting system PB-098

On a flat terrace the panels cannot lie down, because they would produce little and would get dirty, so they need a structure that raises them at an angle. The set does exactly this: triangular frames or front-rear supports of different heights, over which the rails and then the modules are mounted. The bracing elements tie the row together and make it rigid, so that the wind does not shake it.

The feet on which the structure rests have rubber or EPDM mats, which spread the pressure over a larger area and protect the waterproofing of the terrace. You have two fixing methods: by ballasting, with concrete slabs or weights placed on the feet, without drilling the waterproofing at all, or by mechanical anchoring into the load-bearing structure, with subsequent sealing of the penetrations. The choice depends on how much extra weight the slab can carry and on the wind in the area, and at the corners and along the edges the stress is higher, so additional ballast is provided there. The aluminium and stainless steel used do not rust, so the structure has a service life comparable to that of the panels.

Extruded aluminium profiles and stainless steel joining elements, chosen for galvanic compatibility and corrosion resistance on the terrace; feet with rubber or EPDM protective mats for spreading the pressure on the membrane. Configuration with triangular elements or front-rear supports of different heights, longitudinal rails for the modules and stiffening braces. The sizing of the ballast or of the anchors is done according to SR EN 1991-1-4, with values differentiated by corner, edge and inner field zones, taking into account the height of the building and the bearing capacity of the slab.

Who it suits

Suitable for apartment block terraces, office buildings and halls with flat roofs, especially where the waterproofing cannot be pierced and fixing is done with weights.

Terms explained

• Ballasting: Holding the structure in place with weights, usually concrete slabs, instead of screws, so that the roof is not drilled.
• Waterproofing: The impermeable layer on the terrace, membrane or bitumen, that stops the water; any penetration through it must be sealed.
• Bracing: Bars mounted diagonally, which stiffen the structure and prevent it from deforming in the wind.

Technical specifications

Recommended applications

• PV installations on apartment block terraces and office buildings
• Industrial flat roofs with bituminous waterproofing or PVC membrane
• Systems where piercing the waterproofing is not allowed and ballast is used
• Capacity extensions on existing buildings with a concrete slab

Technical details

Generic product — standard specifications

The flat roof mounting system is a support structure that places the photovoltaic modules at a tilt angle on a horizontal surface or one with a very small slope. Constructively, such a kit is made of triangular elements or of front-rear supports of different heights, longitudinal rails on which the modules are clamped and bracing elements that stiffen the row.

The materials used are extruded aluminium for the profiles and stainless steel for the screws and joining elements, a combination chosen for galvanic compatibility and for corrosion resistance in the terrace environment. The bearing feet are provided with rubber or EPDM protective mats, which spread the pressure on the waterproofing and prevent damage to the membrane.

Fixing to the roof is done in two ways: by ballasting, with concrete slabs or weights placed on the feet of the system, a solution that avoids piercing the waterproofing, or by mechanical anchoring into the load-bearing structure, with subsequent sealing of the penetrations. The choice between the two depends on the bearing capacity of the slab and on the wind load calculated according to SR EN 1991-1-4, taking into account the height of the building, the zone and the position within the module field (corner and edge zones require additional ballast).