Introducing terapro® FOS, the revolutionary seamless geomembrane composite designed for waterproofing of a variety of hydraulic structures, ditches, and channels. terapro® FOS stands out as a cutting-edge solution that seamlessly combines performance and ease of application. 

This innovative product is specifically crafted for applications in hydraulic engineering, where the need for impermeable solutions is paramount. The unique design of terapro® FOS ensures a single, cohesive membrane that provides a comprehensive barrier against water seepage, making it an ideal choice for a wide range of projects. 

The terapro® FOS one-piece construction eliminates the need for laborious and time-consuming jointing, ensuring a faster and more efficient installation process. This not only saves time, but also enhances the overall reliability of the waterproofing system. 

Ideal for use in a variety of hydraulic structures, including dams, reservoirs, and canals, terapro® FOS excels in providing long-lasting protection against water infiltration. Its versatility extends to ditches and channels, where a seamless, durable barrier is crucial for preventing soil erosion and maintaining the structural integrity of these essential elements of hydraulic systems.


  • terapro FOS is used in hydraulic structures for ditches and gutters, covered with earth



  • terapro® economical and easy and quick to install
  • the layers joined together at manufacturing in the factory eliminate the need for successive laying of geotextiles and geomembranes and do not slip relative to one another during backfilling
  • flexible, waterproof and continuous, terapro® FOS adapts to the substrate without cracking
  • terapro® FOS protects the subsoil and groundwater from pollution by road runoff water
  • covered with topsoil it fits in with the environment
  • covered with gravel it requires no mowing maintenance
  • joints are treated by welding for a perfect join
  • the terapro FOS range is broad, allowing you to find the appropriate product for your needs


The product consists of needle-punched, nonwoven polypropylene puncture-resistant protective geotextiles of 300 g/m2 mass per unit area, joined in factory by a hot-melt process to a waterproof polyethylene sheet.

Assembly of the waterproof polyethylene sheet should be feasible by hot air gun and with an automatic machine. The dynamic puncture resistance in accordance with ISO 13433 must be less than 1mm, and the static puncture resistance greater than 3.6 kN.

Installation technique

  • prepare a clean, graded, compacted and drained earthworks base with no protruding elements
  • unroll terapro® FOS on the ground with a pole and a machine, or by hand, or use a lifting beam, wearing gloves
  • adjust the fit to the earthworks profile, cut out using a cutting disc if necessary, peg terapro® FOS with concrete reinforcing bars on the edges to hold it in position during backfilling with materials and smooth with a levelling bucket
  • treat tiling joins by thermal bonding with a hot air gun
  • please contact teragéos for any installation advice or technical assistance for bonding


  • terapro® FOS is available in widths of 1, 2 and 4m and 50m lengths; other sizes on request.

Additional information

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