Acoustic comfort as a foundation for daily work
Upon entering the Grodan offices in Roermond, the Netherlands, a sense of familiarity emerges. The colourful, atmospheric canteen echoes an office two floors below, designed earlier for sister company Rockfon. This continuity is intentional. Both interiors were designed by Judith Muijtjens of Wonderful Day Design, and both rely on a composed collection of interior acoustic solutions to support employee comfort.
“The concept is indeed similar, as is the design process. Grodan's employees, like those of Rockfon, provided valuable input during the co-creation sessions,” Judith explains.
While the two projects share a design lineage, Grodan’s office has its own character and requirements. To meet the acoustic standards set by parent company ROCKWOOL Group, a broad range of Rockfon acoustic solutions were specified both as office ceiling design and as wall features.
Employees shaping the brief from the outset
Prior to the renovation, Grodan’s work environment consisted largely of small, enclosed offices with whitewashed walls. The layout no longer supported contemporary ways of working, prompting the company to reflect on how it wanted to operate in the future.
“Grodan asked me to explicitly involve employees in the design process," explains Judith Muijtjens. “We discussed urgent needs in the work environment – especially what kind of atmosphere and feelings a new work environment requires. We discussed in detail how the employees work now and how they would prefer to work.”
These co-creation sessions revealed a clear set of priorities. The new office needed to support inspiration and visual quality, while also offering calm. “While Rockfon has a more dynamic work environment, Grodan employees wanted more privacy, more security, more peace, and more greenery. I incorporated this into the design,” says Judith Muijtjens.
Translating horticultural identity
As a supplier of innovative stone wool substrate solutions for the horticultural sector, Grodan’s professional DNA became a guiding theme for the interior concept. Greenery plays a central role throughout the office, reinforcing a connection to plant cultivation and growth.
The ambition was to create an atmosphere reminiscent of working in a greenhouse. However, a literal greenhouse environment would not meet strict acoustic performance requirements. Instead, garden rooms were introduced. These spaces reference greenhouse structures visually, while glass walls and integrated acoustic measures ensure compliance with ROCKWOOL standards for light, air quality, acoustics, and overall comfort.
Daylight strategies and spatial depth
Grodan’s office occupies the top floor of the building in Roermond, offering valuable access to roof-level daylight. Judith Muijtjens used this condition to enhance the spatial experience across the floorplate.
"Daylight streams into the office spaces from the windows in the facade. However, the central area doesn't benefit from this. By placing meeting rooms and focus rooms beneath the skylights, the entire depth of the office wing can be utilised. This daylighting is more pleasant and enhances the atmosphere of the space," she explains.
The rooflight panelling was installed by Gepla following the renovation of the skylights by the roofing contractor. "After the roofer had renovated the skylights, we began the finishing work. This was a labor-intensive job, partly because Judith wanted to conceal the steel beams," says Project Manager Steve Krijgsman.
Close collaboration on acoustic execution
Drawing on experience from its own recently renovated offices, Rockfon supported Grodan throughout the selection, delivery, and installation of the acoustic solutions.
"Our own renovated ground floor office has become a showcase for our acoustic solutions. It was therefore a natural fit for us to assist our colleagues at Grodan in selecting the right products, and in their delivery and installation," explains Sjraar Billekens, Benelux Marketing Manager at Rockfon.
"Most of our installation work was fairly standard," explains Steve Krijgsman. "We had a lot of discussions with Judith during the project, because translating the design into practice wasn't always easy. The location of Rockfon Eclipse floating ceiling panels was determined in consultation with our installers."
"The suspension systems were also by Rockfon. That was actually very pleasant to work with. We told Rockfon what we needed in terms of ceiling tiles and suspension systems, and the materials arrived from their own factory right on time.”
Gepla also produced two bespoke elements for the project. “We had two rounded corners. The radius of the corners was so small that we couldn't create them with plaster. Our supplier made molds for this and cast these corners with plaster. These were delivered prefabricated to the site, where we installed them.”
A sneak peek into a new acoustic solution
The Grodan project also served as an early application for a new acoustic product. As Sjraar Billekens explains, "Rockfon Timber, in the 12-shuffle-16 D-edge version in Oak, is installed on across the walls. This is a new product in the Netherlands currently only available for small pilot projects, to be officially presented in 2026. It's a wood panel system that offers stone wool acoustic properties with the warmth of wood."
At Grodan, Rockfon Timber is installed as wall panelling in the corridors, though it can also be applied on ceilings. Additional acoustic measures include second-generation Rockfon Canva Wall panels, Rockfon Canva Floor screens between workstations, Rockfon Eclipse Colour floating ceiling panels, as well as Rockfon Color-all and Rockfon Blanka acoustic ceiling tiles.
The walls are further enriched with Rockfon Lamella slatted acoustic systems, alongside Rockfon Senses acoustic wall panels featuring Organoid surfaces with natural pressed flowers.
A workplace designed to grow over time
Reflecting on the completed project, Judith Muijtjens sees a strong alignment between Grodan’s organisational values and the finished interior. Grodan’s DNA – innovative, sustainable, and people-focused – is expressed through an office environment shaped by daylight, greenery, and acoustic comfort.
"Sustainable materials have been used wherever possible. Think of a floor finish with a natural texture and eco-backing, a healthy paint system, and a circular kitchen."
Furniture selection followed the same principles. Upholstery and foam padding for sofas are produced from recycled materials, while much of the existing furniture has been reused. Living greenery is integrated throughout the space. Grodan’s new work environment is truly "Designed to Grow", says Judith Muijtjens.
"In some areas, extra-wide strip grids have been used across the ceiling. If there is a need for them in the future, walls can be installed in those areas to create more enclosed offices."
Gepla also reflect positively on the collaboration. "Judith Muijtjens beautifully translated our wishes into the design, and I must say the end result is impressive. We're truly proud of it. The entire process was enjoyable for us, from furnishing the space to completion. Collaboration was excellent with all parties involved."
