Thesb
Active Member
Thanks AGTO - still, I think people may be making a big deal over what should amount to very little noise variance between design types. A little more context:
STC What can be heard
25 Normal speech can be understood quite easily and distinctly through wall
30 Loud speech can be understood fairly well, normal speech heard but not understood
35 Loud speech audible but not intelligible
40 Onset of "privacy"
42 Loud speech audible as a murmur
45 Loud speech not audible; 90% of statistical population not annoyed
50 Very loud sounds such as musical instruments or a stereo can be faintly heard; 99% of population not annoyed.
60+ Superior soundproofing; most sounds inaudible
STC Partition type
33 Single layer of 1/2" drywall on each side, wood studs, no insulation (typical interior wall)
45 Double layer of 1/2" drywall on each side, wood studs, batt insulation in wall
46 Single layer of 1/2" drywall, glued to 6" lightweight concrete block wall, painted both sides
54 Single layer of 1/2" drywall, glued to 8" dense concrete block wall, painted both sides
55 Double layer of 1/2" drywall on each side, on staggered wood stud wall, batt insulation in wall
59 Double layer of 1/2" drywall on each side, on wood stud wall, resilient channels on one side, batt insulation
63 Double layer of 1/2" drywall on each side, on double wood/metal stud walls (spaced 1" apart), double batt insulation
72 8" concrete block wall, painted, with 1/2" drywall on independent steel stud walls, each side, insulation in cavities
STC partition ratings taken from: "Noise Control in Buildings: A Practical Guide for Architects and Engineers"; Cyril M. Harris, 1994
STC What can be heard
25 Normal speech can be understood quite easily and distinctly through wall
30 Loud speech can be understood fairly well, normal speech heard but not understood
35 Loud speech audible but not intelligible
40 Onset of "privacy"
42 Loud speech audible as a murmur
45 Loud speech not audible; 90% of statistical population not annoyed
50 Very loud sounds such as musical instruments or a stereo can be faintly heard; 99% of population not annoyed.
60+ Superior soundproofing; most sounds inaudible
STC Partition type
33 Single layer of 1/2" drywall on each side, wood studs, no insulation (typical interior wall)
45 Double layer of 1/2" drywall on each side, wood studs, batt insulation in wall
46 Single layer of 1/2" drywall, glued to 6" lightweight concrete block wall, painted both sides
54 Single layer of 1/2" drywall, glued to 8" dense concrete block wall, painted both sides
55 Double layer of 1/2" drywall on each side, on staggered wood stud wall, batt insulation in wall
59 Double layer of 1/2" drywall on each side, on wood stud wall, resilient channels on one side, batt insulation
63 Double layer of 1/2" drywall on each side, on double wood/metal stud walls (spaced 1" apart), double batt insulation
72 8" concrete block wall, painted, with 1/2" drywall on independent steel stud walls, each side, insulation in cavities
STC partition ratings taken from: "Noise Control in Buildings: A Practical Guide for Architects and Engineers"; Cyril M. Harris, 1994