8 concrete block hollow core painted 2 coats 2 sides.
Stc concrete block wall.
A stc rating of 55 is required for inter tenancy walls.
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.
Many sound transmission loss tests have been per formed on various concrete masonry walls.
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.
Standard stud wall with one layer of 16mm 5 8 plasterboard.
These tests have indicated a direct relationship between wall weight and the resulting stc heavier concrete masonry walls have higher stc ratings.
A wall floor or roof.
In general the stl of a concrete masonry wall increases with increasing frequency of the sound.
Typical wall construction with 1 layer of 16mm 5 8 plasterboard on each side of 95x35mm 4 x 11 2 timber studs.
Stc ratings are determined by laboratory tests of a.
Within a dwelling an internal wall with a stc rating of 45 will usually muffle television telephone ringing and conversation in an adjoining room.
Determining sound transmission class stc for concrete masonry.
The higher the rating the greater the degree of noise reduction.