SOUND TRANSMISSION

Acoustic treatment - Sound control between spaces

Minimum STC ratings are required under most building codes for partition walls, corridor walls and floor/ceiling assemblies. The higher the STC number, the greater the sound transmission resistance. A descriptive table outlining the various increments of STC class is shown below.

Changes in STC Rating	Changes in Apparent Loudness
+/- 1 +/- 3 +/- 5 +/- 10	Almost imperceptible Just perceptible Clearly noticeable Twice (or half) as loud

Source: www.acoustics.com website March 2004

Interior sound walls and ceilings

A 37mm / 1.46 inch application of Monoglass has been shown to increase the STC value of an assembly by 5, when tested to ASTM E-90-85. This will make a clearly noticeable difference when compared to an uninsulated wall or ceiling.

The STC ratings of Monoglass insulation are similar to those of fiberglass batt insulations, however, because Monoglass is sprayed in place it will fill voids that batt insulation may not. Also, Monoglass adhesives keep the insulation in place so that it will never settle over time leaving gaps.

Music Room, M.J. Mouat School, Abbotsford, BC. Gordon Graham Architects

Monoglass applied above the drop ceilings to reduce sound transmission into occupied rooms above.