Services

TPO, PVC and EPDM Membrane Roofs

Mechanically fixed synthetic membrane cladding on lightweight metal roofs.

About the system

A synthetic membrane roof is a system developed for low-slope and flat roofs, formed by covering the insulation layer over a lightweight metal deck with a TPO, PVC or EPDM waterproofing sheet. Its main strengths are the speed with which large areas can be closed and the ease of adapting to complex details.

Installation starts with the trapezoidal sheet profile and thickness selected for the steel purlins in the project. After the deck is mechanically fixed, a vapour control membrane is laid over it. Insulation boards of the type and thickness specified in the project are then mechanically fixed onto this layer. As the final layer, EPDM, PVC or TPO membrane is laid with mechanical fixings and the laps are hot-air welded, producing a continuous, leak-proof surface across the roof.

The fixing method is chosen according to wind load and roof use: mechanical fixing is fast and economical, while the fully adhered method leaves no fastener pattern on the surface and performs well in high-uplift zones. A ballasted build-up is preferred on accessible or green roofs where the structure can carry the additional load.

Applications

Logistics warehouses and distribution centres
Production plants and flat industrial roofs
Shopping centres and big-box retail buildings
Terrace roofs of hospitals and public buildings
Large roof areas planned for rooftop solar installations
Overlay refurbishment of existing roofs

Installation process

01
Roof survey and membrane selection
Pitch, drainage layout, wind zone and rooftop equipment loads are assessed; the choice between TPO, PVC or EPDM and the membrane thickness are determined.
02
Deck and vapour control layer
The trapezoidal deck is mechanically fixed and a vapour control membrane is laid over it with sealed laps.
03
Thermal insulation
Insulation boards of the specified type and thickness are laid with staggered joints and mechanically fixed.
04
Membrane laying and welding
The membrane is rolled out, mechanically fixed or fully adhered, and the laps are hot-air welded with an automatic welding machine.
05
Details and outlets
Parapets, expansion joints, penetrations, outlets and rooftop equipment surrounds are sealed with prefabricated corners and hand welding.
06
Weld testing and handover
Every weld seam is probe-tested end to end; after a water test and visual inspection the roof is handed over.

Available materials

TPO (thermoplastic polyolefin) membranePVC (plasticised polyvinyl chloride) membraneEPDM (synthetic rubber) membranePIR / rockwool / EPS insulation boardsVapour control membraneTelescopic fasteners and fixing plates

How do you choose between TPO, PVC and EPDM?

PVC stands out for its resistance to chemicals and oils and for easy welding; TPO contains no plasticisers, so it is dimensionally more stable and its light surface reflects solar heat; EPDM keeps its flexibility over a wide temperature range, which helps on moving details. The choice is made together, based on chemical exposure, detail density and budget.

Mechanically fixed or fully adhered?

Mechanical fixing is faster and more economical and is sufficient for most industrial roofs. Fully adhered systems are preferred in high wind uplift zones, where the fastener pattern must not be visible and where the surface must stay free of fluttering. The decision follows the wind load calculation.

Can solar panels be installed on a membrane roof?

Yes, but the layout must be planned from the outset. Reinforcing pads are needed under the mounting feet, the additional load of ballasted systems must be checked with the structural engineer and walkways must be provided for maintenance. Penetrating fixings added later may affect the warranty.