Acoustical and noise control concerns exist in almost every modern building
Most commonplace acoustical issues are resolved using a consultant's assistance?
An acoustical consultant is usually required for the design of a concert hall or to solve a complicated noise problem.
Most sound is non-complex, generally consisting of continum of frequencies.
Sound is the ear’s response to pressure fluctuations in the air caused by
a vibrating object
a back and forth motion of air particles
none of the above
The lower the TL of an assembly, the greater the sound insulation provided by it
The STC of an assembly can be improved if we make it heavier
STC of a 2 x 4 wood stud wall with ½” gypsum board each side = 37. To improve it, we can…
Add fibrous insulation
Add Foam board
Add Structural insulated panels
NRC stands for
Noise Reduction Corollary
Noise Reduction Coefficient
NO RICE CATHY!
Sound originating within a room can only be reduced by using sound-absorbing materials
Sound-absorbing materials(acoustical materials) have a sound-absorption co-efficient of
<0.2
>0.2
>0.4
<0.4
The sound-absorptive coefficient of an assembly =
the sound energy that is NOT reflected by the assembly divided by the total sound energy falling on the assembly
the sound energy that IS reflected by the assembly divided by the total sound energy falling on the assembly
A closed window is the perfect acoustical absorber because it does not reflect any sound
The sound pressure that corresponds to the sensation of pain in the ear is approx
20 PA
30 PA
10 PA
Although sound pressures are small, their range is extremely large
Massive heavyweight assemblies are horrible sound insulators
What are the 3 basic framing members , ,
Light gauge steel members are increasingly used as blocking/backing for handrails, upper cabinets, or any other secured material or assembly