Achieving BREEAM-Outstanding certification
For PLUS, centralising distribution and replacing four centres with a newly developed mega centre was an opportunity to think sustainability into every aspect of the construction. Built in the industrial area of Vorstengrafdonk, west of Nijmegen in the Netherlands, and spread over more than nine hectares of land (that’s 19 soccer pitches!) the massive building is 30 metres in height and spans more than 46,000 m2. With 92 loading bays and a production capacity of 400,000 packages per day, the distribution centre serves 270 PLUS supermarkets all over the Netherlands. Creating more sustainable distribution is clearly better for business and the environment, but storing all supplies in one location brings new risks and concerns.
An added risk was the fact that the roof would be covered in 11,000 solar panels to produce clean energy onsite. A recent study completed by the University of Edinburgh highlighted that solar panels can act as an ignition source for flat roof fires as well as adding to the fire load, increasing the fire spread and intensity.
To achieve the Outstanding certification, the project must reach a BREEAM score of at least 85 percent through demonstrating a creative approach to sustainability and utilising the highest-quality technologies and design concepts. The distribution centre successfully achieved the BREEAM Outstanding certificate, and stone wool played an important part, with ROCKWOOL flat roof and metal box insulation installed.
The BREEAM certification is based on nine sustainability categories, and the ROCKWOOL products used contributed to four of these.
The four categories to which the ROCKWOOL products contributed to are:
Based on one of the most abundant raw materials on the planet, ROCKWOOL stone wool is circular by nature, and fits seamlessly into PLUS’ sustainable ambitions.
“Everything that contributes to the new distribution centre being built as sustainably as possible is important for us”, explains Tinie Dorresteijn. “Choosing ROCKWOOL insulation is part of this, so the recyclability of ROCKWOOL stone wool insulation is a clear advantage for us”.
Stone wool insulation contributed significantly to the distribution centre’s excellent BREEAM score. Lasting for 55+ years (and counting!), stone wool can easily be removed when a building is renovated, or demolished and recycled back into new products. In fact, stone wool can be recycled again and again into new stone wool.
According to Dorresteijn, the natural fire resilience built into stone wool was another important reason for PLUS to choose ROCKWOOL.
“Our fire safety must be at the highest level…. By choosing stone wool and installing of sprinklers, this has been taken into account," says Dorresteijn.
Hollanddak, the roofing partner for the project, had a clear preference when it was decided that stone wool was the material of choice for the distribution centre.
“We have little influence on the choice of material; we have to respect the specifications we get," says Erwin van Os, director at Hollanddak. "But as far as stone wool insulation is concerned, we only work with ROCKWOOL. We know the quality of its products and trust the service and the organisation. ROCKWOOL flat roof insulation is non-combustible, pressure and shape resistant, stable and very durable. These are all characteristics that are important for both a client and building user, but also for the insurer who wants to run as little risk of damage as possible.”
For Hollanddak, the ROCKWOOL flat roof product used, known locally as Caproxx Energy, was then the logical choice to insulate the enormous flat roof. As a roofer, it is key to ensure that the space is wind and waterproof as quickly as possible.
“We prefer that no one walks over the roof just after the insulation has been installed, but that was an illusion with this project”, explains Van Os. “There was considerable foot traffic just after the insulation was installed due to further technical installations needed. But the insulation we used is sufficiently pressure-resistant and stable with a high point load, so this wasn’t an issue”.
Hollanddak was in contact with ROCKWOOL’s technical department to discuss the fact that the distribution centre’s roof would be covered with 11,000 solar panels. The fact that the flat roof insulation is based on non-combustible stone wool means that it is fire resilient by nature, withstanding temperatures of over 1000 °C, containing fire and preventing its spread.
“ROCKWOOL has written a processing guideline for the application of flat roof insulation in combination with solar panels. We made use of that”, says Van Os. "When necessary, ROCKWOOL representatives attended the construction meetings, so that we could always ask questions or request information. We have a good partnership with them”.
In fact, many insurance companies recommend the use of non-combustible insulation materials in conjunction with solar panel installations, with some large companies and building owners insisting that ROCKWOOL roofboard insulation be used in such cases.
The PLUS distribution centre project is in its final stages, with the logistical equipment and mechanisms currently being tested. It is expected to be fully operational in early 2023. But with the BREEAM Outstanding certification already under its belt, it seems certain to have a bright and sustainable future ahead.
Construction period : 2020 - 2022
Roof area : 46,000 m2
Solar panels: 11,000
Client: PLUS
Architect: Da Vinci
Main contractor: Construction company Van de Ven
Roofer: Hollanddak
BREEAM consultant: C2N
Foto: © Walter Frisart FOTOwerk