Sound transmission class stc provides an estimate of the acoustic performance of a wall in certain common airborne sound insulation applications.
Stc of concrete block wall.
Stc hollow with insulation 52 53 56 59 corefoam masonry foam insulationis an excellent product for improving thermal and acoustic properties of walls constructed with concrete masonry units cmu.
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.
The sound transmission class stc is a single number rating of a material s or an assembly s ability to resist airborne sound transfer at the frequencies 125 4000 hz.
1 contains procedures for determining stc values of concrete masonry walls.
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.
Tek 13 1c sound transmission class ratings of concrete masonry walls contains a complete discussion on determining stc ratings applicable building code requirements as well as tabulated values for various concrete masonry walls.
In general a higher stc rating blocks more noise from transmitting through a partition.
The stc of a wall is determined by comparing sound transmission loss stl values at various frequencies to a standard contour.
Mate the stc for concrete ma sonry walls based on their weight.
8 concrete block hollow core no wall finish.
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.
Standard stud wall with one layer of 16mm 5 8 plasterboard.
Estimated stc ratings for cmu walls the stc rating of a cmu wall can be estimated based on its weight using the following formula.
Stc is highly dependant on the construction of the partition.
Stc 20 50 234w eqn.
Determining sound transmission class stc for concrete masonry.
Typical wall construction with 1 layer of 16mm 5 8 plasterboard on each side of 95x35mm 4 x 11 2 timber studs.
8 concrete block hollow core painted 2 coats 2 sides.
Stc 0 18w 40.
Stc ratings for concrete masonry walls are determined using standard method for determining the sound transmission class rating for masonry walls tms 0302 ref.