The Solidaris building is set to undergo an energy-efficiency upgrade, without altering its structure

With energy prices on the rise, it is becoming increasingly worthwhile to invest in extra insulation. This can lead to a drastic reduction in energy consumption, particularly in older buildings. Solidaris also wanted to give its 1980s building an energy-efficiency upgrade to reduce heating costs.

First item on the agenda? The roof structure. For this project, Solidaris commissioned the contractor SIX by Tectum from Izegem.

Stepped architecture

The building’s stepped architecture presented the first major challenge.

Isabelle Van Gucht, project manager at Six by Tectum on the Solidaris Kortrijk construction site:

The building’s design made it difficult to deliver the insulation material. The entire building is stepped in design. This means you have to reach out at an angle, which is by no means easy. Fortunately, after a great deal of trial and error and thanks to our experienced roofers, we managed to get the insulation material into place fairly smoothly after all.

Overcoming the need for structural alterations with vacuum insulation

The second, and biggest, challenge in this renovation was the window and door openings. The sills of these openings are a certain height. If you add extra insulation there, as in other places, the waterproofing will no longer be effective. Isabelle: “We soon realised that vacuum insulation would be the most suitable solution here. We opted for Deck-VQ vacuum insulation panels from Recticel Insulation. This insulation is very compact, yet has an exceptionally high insulation value. As a result, we did not need to carry out any costly structural alterations to the windows and doors – something the client had specifically requested.”

The majority of the flat roofs are insulated with Eurothane Silver insulation boards (two layers of 81 mm, staggered on top of each other). The existing roof pitch, designed to facilitate drainage, was retained, allowing the new, additional insulation to be easily fixed to the existing roof structure. The flat roofs were originally insulated to a very limited extent with cellular glass insulation. With an RD value of 7.30 m²K/W for both layers of Eurothane Silver, the building is ready for the future!

Solar panels on the roof

The Solidaris building is the oldest building in the President Kennedy Park business park in Kortrijk and sets an example for all the other buildings on the site. Solar panels will also be installed on the roof at a later stage. This will complete the energy-efficiency overhaul.