Stc Concrete Walls

Sound transmission class the decibel db is used to express sound intensity or loudness the more intense a sound the higher the db level the sound transmission class stc is a numerical rating of the ability of a wall floor ceiling assembly or any other building element such as a door or window to minimize sound transmission.

Stc concrete walls.

The stc can be used to measure sound absorption for both external building walls and internal walls in single and multifamily structures. 1 contains procedures for determining stc values of concrete masonry walls. Concrete is the standard building material for a reason. Sound transmission class stc provides an estimate of the acoustic performance of a wall in certain common airborne sound insulation applications.

All too often this plenums and suspended ceilings unbaffled ducts window to window outdoors common heating units transoms and air grilles unblocked joist spaces uncaulked wall perimeters ducts piping and fixtures masonry joints. For example a thick concrete wall will block more sound than a thin gypsum 2x4 wall. Determining sound transmission class stc for concrete masonry. The calculation in tms 0302 is based on a best fit relationship between concrete masonry wall weight and stc based on a wide range of test results.

Comply with fire resistance requirements under evaluation reports of ul u336 weigh at least 50 less than masonry walls allowing faster easier installation for more information see the following brochures. How soundproof is concrete. Superior walls precast concrete foundations are the best solution for residential builders looking for reliable scheduling efficient one day installation ready to finish convenience energy code performance and a manufacturer s limited warranty. Mass is commonly added to existing walls by adding additional layers of gypsum.

Estimated stc ratings for cmu walls the stc rating of a cmu wall can be estimated based on its weight using the following formula. When the mass of a barrier is doubled the isolation quality or stc rating increases by approximately 5 db which is clearly noticeable. Stc 20 50 234w eqn. Drywall and plaster are simple to affect and you can produce holes with minimal effort.

According to the standard stc can be determined by field or laboratory testing in ac cordance with standard test methods or by calculation. Usg area separation walls achieve up to 60 stc offer 2 hr. Stc 0 18w 40. The standard requires a minimum laboratory stc rating of 50 for party walls and floor ceilings.

Stc ratings for masonry cmu walls is based on weight of the block and whether the cells are filled or not and what material it is filled with. The stc of a wall is determined by comparing sound transmission loss stl values at various frequencies to a standard contour.