The standard requires a minimum laboratory stc rating of 50 for party walls and floor ceilings.
Stc 50 concrete wall.
To view different wall assemblies click on each point below that may apply to your project.
Acoustic standards guidelines and building rating systems require an stc 50 rating between rooms such as classrooms 1 conference rooms 2 3 executive offices 2 patient exam rooms treatment rooms and consultation rooms 4.
Staggered or double stud walls are higher rated than single stud walls.
These wall assembly files are used for planning and estimation purposes for many ul wall types such as fire rated wall assemblies.
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.
Best blocking stc 50 full height walls preferred a sound blocking level of stc 50 means that a listener in a quiet room would need to exert effort to hear raised speech levels in adjacent rooms and the speech would not be understandable or disruptive.
However the additional weight added complexity of construction and poor thermal insulation tend to limit masonry wall partitions as a viable sound isolation solution in many building construction projects.
Metal stud walls perform better than wood stud walls.
50 stc with single layer designs have achieved up to 4 hr.
14 mm deep 28 gauge 15 mils corrugated steel and 2 1 2 64 mm concrete slab.
Furring channels may be attached to 1 1 2 38 mm cold rolled channels 48 1219 mm o c.
Lateral bracing on both sides of the wall not less than 5 feet on center vertically.
Insulation will noticeably improve the stc rating of an assembly.
Determining sound transmission class stc for concrete masonry.
Sound transmission class stc provides an estimate of the acoustic performance of a wall in certain common airborne sound insulation applications the stc of a wall is determined by comparing sound transmission loss stl values at various frequencies to a standard contour stl is the decrease or attenuation in sound energy in db.
Stc ratings for wall floor and window materials and assemblies 3 appendix a stc ratings a 1 walls a 1 exterior a 1 interior a 9 wooden studs a 9 metal studs a 14 floors a 16 wood a 16 concrete a 21 windows a 24 doors a 27 exterior a 27 interior a 29 appendix b references b 1.
Due to increased mass poured concrete and concrete blocks typically achieve higher stc values in the mid stc 40s to the mid stc 50s than equally thick framed walls.
Horizontal joints on opposite sides need not be staggered.
Stc 0 18w 40.
The stc rating of a cmu wall can be estimated based on its weight using the following formula.
