Non-combustible insulation that perfectly supports solar panel installation

The challenge

When Hoberg & Driesch, one of the leading European wholesalers for steel tubes, decided to establish its company headquarters and warehouse in Düsseldorf-Rath, its goal was to create an energy efficient facility that used renewable energy whenever possible. The company was aware that solar panels are an excellent way to produce clean energy directly onsite. With the warehouse spanning

30,000 square meters, mounting solar panels on the flat roof was a great way to partially supply renewable energy to both the warehouse and the administrative building.

But there are a number of challenges associated with installing solar panels on flat roofs, namely fire safety and risks involving the additional mechanical load. Solar panels can act as an ignition source for flat roof fires, and can radiate heat back to the roof structure increasing the fire spread and intensity. The mechanical loads impacting the integrity of the roof structure also need to be carefully considered when designing the new roof.

The solution

ARGE “Frauenrath – Imtech BV Hoberg & Driesch”, the project’s contractor, ensured that everything ran smoothly. The team understood that careful planning and execution were key to the construction of the flat roof. This involved creating a detailed execution and laying plan that focused on different zones within the roof area. An expanse of 29,000 m² had limited mechanical requirements and was fitted with ROCKWOOL Durock, a pressure-resistant stone wool insulation featuring unique dual density technology. Roofing specialists, Bernd Baltes Bedachungen from Wegberg,  chose to install ROCKWOOL Megarock on the remaining 900m². As this area would be subjected to higher loads from the solar panel installation and its maintenance, ROCKWOOL Megarock was the perfect match, being a roofboard specifically designed for such a high demanding application.

Strong, stable and easy to process

The combination of highly compressed, pressure-resistant stone wool insulation with a fibre-reinforced inorganic coating makes for a very resilient material – also in terms of its load-bearing capabilities. This meant that the roof structure within the more heavily loaded zones only needed slightly more structural support than the rest of the roof, simplifying the integration of the entire roof. Even though stone wool insulation is a strong and durable material, it could be easily processed and cut using a hand saw.

To highlight the correct walkway to take, the maintenance route was sealed using a different colour. But the strength of stone wool meant that no further, more elaborate load-measures were needed. If a less resilient material was used, concrete slabs or other reinforcing solutions would need to be installed on top of the roof membrane, creating height differences within the roof construction which can create drainage issues during rainy periods.

The excellent thermal properties of the stone wool insulation elevated the energy efficiency of both the headquarters and warehouse, helping significantly minimise operating costs. In summary, the flat roof insulation solutions from ROCKWOOL proved to be the perfect match for Hoberg & Driesch’s needs, securing superior thermal, sound and fire protection for its development in Düsseldorf.