'Quality prevails'

The new construction of the RIVM/CBG headquarters involves 21,000 m² of roofing work. On all building parts, Winans Dakwerken is providing the roof insulation, roofing and roof superstructures. The roofing contractor's quality assurance system, used in a previous project for the Rijksvastgoedbedrijf, was taken as the guiding principle in Utrecht, with extensive quality testing due to the contract duration.

Winans' quality assurance system was previously used successfully during new construction for EMA, Harjo Wind says. "It includes an initial internal inspection for quality and control of certification of materials. Then the contractor inspects the assembly and finally we have an external party do another inspection, partly in connection with insurance, after which guarantees can be issued. This has gone down well with the client and is also being applied here, partly because we want to be ahead of the Wkb and because this project will remain under contract with the construction consortium for 25 years."

The RIVM building is special in this regard because the lab areas must be vibration-free. "In the assembly, the functioning of the building had to be taken into account. Based on the principle of walkable roofs, multi-layer bituminous roofing was chosen here. There are 7 building sections, with different requirements and diverse use of the roofs. For example, some roof surfaces are finished as green roofs in close cooperation with the green contractor, while others are tiled. We also provide the roof insulation and vapor control layers, as well as roof structures such as eaves and fall protection. The result is a project driven by quality of materials and extensive quality testing."