The roof renovation provided an opportunity to investigate the circular use of materials and the service life of roof membranes.

The ageing roof waterproofing was replaced with new, white reflective roofing. In addition to improving the structural and energy performance, the project also provided opportunities for scientific research into the reuse of insulation materials and the service life of roof membranes.

From preliminary research to renovation

The project began with a thorough analysis of the existing roof structure and the development of various renovation scenarios. The research revealed that the roof waterproofing and the protective coating were severely deteriorated. The existing rock wool insulation, on the other hand, was still in relatively good condition, depending on its location.

Bureau Bouwtechniek examined three scenarios: a complete refurbishment with PIR insulation, a complete refurbishment with rock wool insulation, and a partial refurbishment retaining the existing insulation. In doing so, energy performance, fire safety, technical feasibility, costs and opportunities for material reuse were weighed up against one another.

Based on this preliminary study, a renovation programme was launched, which has since been successfully completed.

The renovation in practice

During the renovation, approximately 1,660 m² of the existing roof structure was replaced with new, white reflective roofing. This limits the heating of the roof surface and thus helps to reduce the heat island effect. Furthermore, the lower surface temperature can have a positive impact on the efficiency of the planned solar panels. This prepares the roof for an additional function as an energy-generating roof, also known as a ‘yellow roof’.

In addition, water drainage was improved by installing additional emergency overflows. The existing lifeline was replaced with a collective fall protection system, ensuring that future maintenance work can be carried out more safely.

Roof renovation as practical research

A distinctive feature of this project is the link between the renovation works and two scientific studies.

Reuse of rock wool insulation – Ghent University

As preliminary research showed that part of the existing rock wool insulation was still in good condition, a study into its reusability, carried out in collaboration with Ghent University, was included in the tender specifications. During the works, insulation boards were removed from carefully selected locations for further investigation. Among other things, this involves examining the effect of moisture on the insulation’s properties and the extent to which reuse is technically feasible.

Service life of roof membranes – Buildwise

Buildwise also used the renovation as a case study for research into the service life of roof membranes in the context of climate roofs and water retention. Material samples were taken from the existing roof waterproofing to investigate, amongst other things, the influence of the existing coating on the ageing and service life of the membrane.

As a result, the roof renovation not only delivered a technically improved and future-proof roof, but also provided valuable research materials that can contribute to a better understanding of circular construction and sustainable roof structures.