Which acoustic tiles absorb best?+
Per millimetre of build-up, mineral wool leads: common ceiling tiles reach αw 0.90 to 1.00 (class A). Wood wool boards and perforated gypsum sit at 0.40 to 0.90 depending on the build-up, offering more robust or seamless surfaces in return. What counts is the measured value of the actual product in its actual mounting.
What is the difference between porous and perforated boards?+
Porous boards (mineral wool, PET, wood wool) absorb inside the material and are broadband. Perforated boards (gypsum, wood, metal) act together with the cavity as a tuned system and can be designed for specific frequency ranges via open area and cavity depth, with a closed, robust surface.
What does the mounting type mean for the measured values?+
The αw applies only to the tested build-up. Ceiling tiles are measured to ISO 354 in mounting type E with a defined cavity, stated in millimetres (E-200 = 200 mm to the slab). An E-400 value cannot be transferred to a directly glued installation; the cavity mainly improves low frequencies.
Are acoustic tiles non-combustible?+
Mineral wool and gypsum tiles usually are (A1/A2). Wood wool boards mostly reach B-s1,d0, mineral-bonded versions up to A2. PET felt is usually B to C (flame-retardant). Escape routes and many public areas require A classes; the class is on the datasheet and filterable in the catalogue.
What does good room acoustics with tiles cost?+
The range is wide and depends on material, surface and installation. A different calculation helps for orientation: a tile with αw 0.9 needs only two thirds of the area of a tile with αw 0.6 for the same effect. A higher-grade product can therefore be cheaper per square metre of effect than the nominally cheaper one.
NRC or αw: which figure counts?+
In Europe αw per ISO 11654, derived from an ISO 354 reverberation-room measurement. The US figure NRC averages differently and runs systematically somewhat higher; the two are not directly comparable. Most robust for planning are the per-octave absorption values from which both single numbers derive.
Can I lay acoustic tiles into an existing grid ceiling?+
Yes, that is the easiest retrofit: swap existing lay-in tiles for absorbing mineral wool tiles in the same module. The substructure stays, and the effect corresponds to the new tile's measured value at the existing suspension depth.
Which boards suit sports halls?+
Wood wool boards are the standard: robust, tested impact-resistant versions available, with αw up to about 0.90 depending on the build-up. Mineral wool tiles absorb more but need mechanical protection in ball-impact areas, such as a perforated metal or grid cover.
