Engineering ToolBox - Resources, Tools and Basic Information for Engineering and Design of Technical Applications!

Sound Transmission through Massive Walls or Floors

Sound transmission and attenuation in building elements like massive concrete walls or floors.

Sponsored Links

The sound transmission through a massive wall or floor depends primarily on the mass of the construction.

Mean attenuation through a massive construction is indicated in the diagram below:

Sound attenuation - massive walls floors

Note! - more mass - more attenuation!

The attenuation for a specific frequency can be calculated by adding the value in the table below to the mean value indicated in the chart above.

Attenuation Correction
-13 -9 -5 -1 3 7 11 15

Note! - higher frequency - more attenuation!

Example - A Concrete Floor and Sound Attenuation

Sound transmission massive floors

The mass m of a concrete floor with density 2300 kg/m3 and thickness 0.2 m can be calculated as

m = (2300 kg/m3) (0.2 m)

    = 460 kg/m2

From the chart above the mean sound attenuation for the floor can be estimated to

52 db

The attenuation dL at 250 Hz can be calculated as

dL = (52 db) + (- 5 dB)

    = 47 dB

The attenuation at 2000 Hz can be calculated as

dL = (52 db) + (7 dB)

    = 59 dB

Sound Transmission Loss - or Attenuation - for some typical Building Elements

Building ElementSound Transmission Loss
- STC Rating1) -
230 mm brickwork, plastered both sides 55 Shouting not audible
Standard 38- by 89-mm (nominal 2- by 4-in) wood studs with resilient channels nailed horizontally to both sides with 20-mm (5/8-in) gypsum wallboard screwed to channels on each side 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 (5/8-in) gypsum wallboard nailed to both sides of standard 38- by 89-mm (nominal 2- by 4-in) studs 40 Loud speech audible but not intelligible
75 mm timber suds, 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

1) STC - Sound transmission class is the USA rating used to characterize airborne noise insulation. A wall system with higher STC rating is more effective in preventing the transmission of sound.

Sponsored Links

Related Topics

Related Documents

Sponsored Links

Engineering ToolBox - SketchUp Extension - Online 3D modeling!

3D Engineering ToolBox Extension to SketchUp - add parametric components to your SketchUp model

Add standard and customized parametric components - like flange beams, lumbers, piping, stairs and more - to your Sketchup model with the Engineering ToolBox - SketchUp Extension - enabled for use with the amazing, fun and free SketchUp Make and SketchUp Pro .Add the Engineering ToolBox extension to your SketchUp from the SketchUp Pro Sketchup Extension Warehouse!

About the Engineering ToolBox!


We don't collect information from our users. Only emails and answers are saved in our archive. Cookies are only used in the browser to improve user experience.

Some of our calculators and applications let you save application data to your local computer. These applications will - due to browser restrictions - send data between your browser and our server. We don't save this data.

Google use cookies for serving our ads and handling visitor statistics. Please read Google Privacy & Terms for more information about how you can control adserving and the information collected.

AddThis use cookies for handling links to social media. Please read AddThis Privacy for more information.


This page can be cited as

  • Engineering ToolBox, (2008). Sound Transmission through Massive Walls or Floors . [online] Available at: [Accessed Day Mo. Year].

Modify access date.

. .


3D Engineering ToolBox - draw and model technical applications! 2D Engineering ToolBox - create and share online diagram drawing templates! Engineering ToolBox Apps - mobile online and offline engineering applications!

Scientific Online Calculator

Scientific Calculator

3 30

Sponsored Links