Sound Transmission through Massive Walls or Floors

Calculate sound attenuation through massive walls or floors based on material mass and frequency. The attenuation depends primarily on the mass of the construction, with higher mass providing greater sound insulation.

Calculator

Inputs

Material Density (kg/m³)

Thickness (m)

Results

Mass per Unit Area-- kg/m²

Calculator

Inputs

Mean Sound Attenuation (dB)

Frequency

Results

Sound Attenuation at Frequency-- dB

Building Element	STC Rating (dB)	Privacy Level
230 mm brickwork, plastered both sides	55	Shouting not audible
Standard 38x89 mm wood studs with resilient channels and gypsum wallboard	50	Shouting barely audible
230 mm brickwork, plastered one side	48	—
115 mm brickwork, plastered both sides	47	—
100 mm timber studs, plasterboard both sides, quilt in cavity	46	Loud speech barely audible
6 mm double glazing, 100 mm air gap	44	—
75 mm clinker concrete block, plastered both sides	44	—
115 mm brickwork, plastered one side	43	—
Two layers of 20 mm gypsum wallboard on 38x89 mm studs	40	Loud speech audible but not intelligible
75 mm timber studs, plasterboard both sides	36	Loud speech audible and fairly understandable
6 mm single glazing	29	Normal speech audible but not intelligible
One layer plasterboard	25	Normal speech easily understood

Frequency (Hz)	Attenuation Correction (dB)
63	-13
125	-9
250	-5
500	-1
1000	3
2000	7
4000	11
8000	15