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Composite tops

Published on 12/09/2019
Deksel in composiet

Tops for sewerage applications are constructed standard of cast iron. These are certified under the COPRO quality mark, or under the BENOR quality mark in the case of tops for roads.

There is a market trend toward the use of tops in composite (plastic).


Composite tops have important advantages. They are considerably lighter than cast iron products and therefore more ergonomic, they have higher corrosion resistance, and are radiation-permeable (for telecom applications).

COPRO certification of composite tops

The certification of composite tops under the COPRO quality mark must be done in accordance with the European standard NBN EN 124-5. This standard applies to tops for manholes and gullies in vehicular and pedestrian areas. Part 5 concerns grates and covers for manholes and gullies made of composite materials. After this standard was revised, COPRO began preparations for certification of tops in composite materials. Partly at the request of producers and suppliers, an advisory board was set up to establish the certification rules.

The meetings of this advisory board resulted in the Application Regulation TRA 33 for product certification of tops made of composite materials for manholes and gullies in vehicular and pedestrian areas. This TRA has been in force since 13 November 2018.

Public and private developers therefore are able to prescribe composite tops with the COPRO quality mark.

Future: BENOR certification of composite tops for roads

Since it is also permitted to use the tops in composite materials in road applications (class D400 according to the NBN EN 124-1 standard), administrations are requesting that additional technical specifications be established on top of NBN EN 124-5. This certification will be done under the BENOR quality mark.

COPRO therefore hopes in the short term to see these technical specifications, also discussed during the meetings of the advisory board, laid down in a PTV so that in the future quality, certified composite tops for roads can be offered on the market.