GypsumHighly absorbent

Physikalisch-Technische Bundesanstalt

Source: Dalenbäck, Datensatz der CATT-Software, November 2000. Data-Category in CATT: PLASTER9, C: Ceilings, D: Perf.

Value from the PTB table, not verified

Ceilings, perf. 27 mm gypsum board (16%), d = 4.5 mm 300 mm from ceiling (CATT: PLASTER9)

PTB reference data

Original description

Material properties

Thickness: 27 mm

Wall distance: 300 mm

Perforation: 16%

Hole size: 4.5 mm

ISO 354 – reverberation chamber

α_w

0.70

α_p nach ISO 11654

f (Hz)	125	250	500	1k	2k	4k
α_p	0.45	0.55	0.60	0.90	0.85	0.75

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Value from the PTB table, not verified

Measured values as a table (1 measurement)

Ceilings, perf. 27 mm gypsum board (16%), d = 4.5 mm 300 mm from ceiling (CATT: PLASTER9): sound absorption coefficient αs per ISO 354 by frequency and test build-up
Build-up	α_w	125 Hz	250 Hz	500 Hz	1000 Hz	2000 Hz	4000 Hz
Measurement 1	0.70	0.45	0.55	0.60	0.90	0.86	0.75

Measured values as a table (1 measurement)

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Last updated: 02/09/2026