General information

  • Location address
  • Location country
  • Year of construction
  • Name of the client/building owner
    SIAAP (Association of regional authorities for waste-water diposal in the Paris region
  • Function of building
    Industrial buildings
  • Degree of enclosure
    Fully enclosed structure
  • Climatic zone
    Temperate - cold winters and mild summers
  • Primary function of the tensile structure
    • Rain protection
    • Space defining elements
    • Sun protection


The architectural style of Valenton is based around the demands of the highly advanced technologies used for the treatment of waste-water. The SIAAP consequently took a sample of the architectonic textile for thorough analysis before it was installed. The observations were based on a retroactive period of 10 years. These specific tests confirmed the suitability of the Fluotop® T membrane for the waste-water treatment environment. What is original about this project is the degree of transparency and light throughout the infrastructure.

The ongoing extension works for the treatment plant at the Valenton site (Val de Marne, France), aim at doubling the volume of sewage treated. Ten circular reservoirs are to be covered with metal/textile structures of about 56 meters in diameter and 5.1 meters in height at the fabric summit. The primary metal structure is made out of double chord arches positioned perpendicular to each other. These arches cater for the suspension of a circular top hoop, which acts as a ridge between the two main fabric fields. The textile surface is divided by the circular ridge into two main fields - an outer zone of about 1750 m² shaped as a truncated Chinese hat, and an inner zone of about 750 m² shaped as an impluvium. Both are made from pre-stressed FERRARI fabric 1302 Fluotop T.In (http://T.In) addition, specific fabric fields are set to cover the internal circulation
pathways and their connections to the main membrane (operculum modules onto bolt cables), as well as to guarantee the closing of maintenance doors and windows (oriel windows and lower skirting).

Description of the environmental conditions

The wind factor has to be taken into account. The acceptable limit for spreading the made up membrane is 10m/second, i.e. 36km/hour.

The objective in extending this waste-water purification plant: To double the treatment capacity at the Seine Amont site (815,000 m2 in the Val de Marne) in order to reach 600,000 m3/ day, by around 2005. In the Paris region: 8.2 million inhabitants are directly affected.

Fluotop® T also provides a Surface treatment that is ideal for the specific requirements of a waste-water tank cover? argues Yves Chauvin.
It recovers odours via a collection phenomenon and prevents gases from escaping. As the tank remains sealed, the vapours remain confined before they are treated and disposed of.

Other properties of the textile:

Its treatment limits dirt deposits and facilitates maintenance. It is a real Anti-dirt shield and its resistance to pollution is significantly superior to that of traditional coverings.

General comments, links

Duration of work: August 1999 ? July 2005

Cost: 38 million Euros (inc. Vat)

Price estimate for the entire roof (framework, canvas and installation) per tank:
Between 1.20 and 1.52 million Euros (inc. Vat).

Material of the cover

  • Cable-net/Fabric/Hybrid/Foil
  • Type (code)
    Ferrari 1302 Fluotop
  • Material Fabric/Foil
  • Material coating
  • Weight (g/m2)

Main dimensions and form

  • Covered surface (m2)
  • Maximum height (m)
  • Total length (m)
  • Total width (m)
  • Form single element
  • Form entire structure

Duration of use

  • Temporary or permanent structure
  • Design lifespan in years

Involved companies