Upholstered panels are the basic infill in office systems. They consist of a core of rigid foam or mineral wool covered with fabric. Foam with a density of 30–40 kg/m³ reaches an absorption coefficient of α = 0.60–0.75 for 32 mm panels. Mineral wool gives α = 0.80–0.90 for 50 mm panels.
The fabric is chosen from the manufacturer's palettes or supplied by the customer (customer's own material, COM). Fabrics are available that are abrasion-resistant, antibacterial, antistatic and flame-retardant in accordance with EN 1021. The colour can be matched to the company's branding to a specific RAL or Pantone shade.
Glass serves an aesthetic and visual function, not an acoustic one. It lets light through and creates a sense of openness while still separating a zone. The thicknesses used are 6 mm in System 20 and 10 mm in System 32. Laminated VSG glass with a PVB interlayer is safer (it does not shatter when broken) and insulates slightly better acoustically (Rw = 30–33 dB vs 26 dB for monolithic glass).
Available glass types: clear, satin (translucent with a matte texture), frosted (opaque), printed (graphics, logos, patterns) and electrochromic (dimming on demand).
Glass does not absorb sound. In a mixed configuration (some panels glass, some upholstered) you should ensure that the absorbing materials make up a sufficient share of the total surface.
Panels of perforated steel or aluminium filled with an acoustic insert offer a combination of industrial aesthetics with an absorbing function. A 3 mm perforation on a 5 mm grid with a mineral wool insert gives α ≈ 0.55–0.65. Sheet metal without perforation does not absorb but does insulate (Rw up to 28–32 dB depending on thickness).
Aluminium is lightweight, corrosion-resistant and available in anodised or powder-coated finishes in any RAL colour.
Three questions decide it: do you need sound absorption (fabric), visual privacy with light transmission (glass), or industrial aesthetics with moderate absorption (perforated metal)? In practice, mixing works best: the lower part of the panel upholstered (absorption), the upper part glass (daylight and a sense of space).