STC: How It Works

Sound is everywhere. When it comes to hotel meeting rooms, classrooms, or office conference rooms, controling sound is a monumental task. Unless a person deals with sound management everyday, it can be difficult to understand what it really means to sound proof. Please watch the following video that gives a basic explanation about what STC Rating mean for spaces with operable partitions. 

Simply put, STC stands for Sound Transmission Class. It is a system that measures how well a wall, door, or other material reduces how much sound gets from one area to another. Sound is a wave. It moves through and around everything. It takes a lot of engineering to keep sound from passing through different materials and miniscule openings. 

In order to earn an official STC rating that's certified, the wall has to be tested a laboratory where evaluators know for certain that sound cannot pass through the surrounding drywall, ceiling, or flooring. When the operable partition is set up and tested, the evaluators measure the decibels that go from one room (where the sound originates) to the next room. This provides the STC rating. 

The video will show that in a functional setting, such as a hotel ballroom, sound in one half of the room will wave out from the noise sources. The sound stays mostly inside the room. However, the sound also travels outside the room allbeit to a lesser extent. The sound finds the weaknesses in sound proofing and passes through. This can be through the ceiling, the flooring, surrounding fixed walls, and the door. Sound can move through the operable partition as well. However, we know from the STC rating how much that will be. 

STC Rating: 
As sound becomes louder, it registers at a higher decibel. A quiet whisper can range from 1 to 10 decibels. Normal conversation level ranges from 20 to 40 decibels. An office that's throwing a party ranges from 60 to 80 decibels. 

Let's say that an operable partition has an STC rating of 48. This means that if one half of a room has noise, the other half of the room will only be able to hear a person talking loudly, but it won't be intelligible. It'll sound like a Charlie Brown, "Wah wah." 

Not every room that's divided up by an operable partition needs a wall with a high STC rating. Not every budget can accomodate a high STC wall either. However, if what the space currently has is not cutting it, contact us. We can perform a service and inspection on the wall to see if the panels have shifted out of plumb, replace broken or missing parts, and more. If more drastic measures need to be taken, updating the panels to something with a higher STC is doable. 

However, many times, a sound issue stems from the areas surround the operable partition and not the folding wall. This would require the consulation of a sound engineer. 

To talk further about your sound needs, please contact us here.