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What are STC Ratings for Glass?

United Plate Glass | Jul 5, 2023 | Blog
What are STC Ratings for Glass?

Glass is a durable and light-transmitting material for interior and exterior walls. But what about sound? Is it possible for glass walls to block sound and reduce noise? Yes. Glass manufacturers use Sound Transmission Class (STC) ratings to define how well glass can dampen ambient sound. When installing glass wall systems, here’s what you need to know about STC ratings and sound transmission.    

STC and Sound Dampening

In a nutshell, standard glass and single-pane glass will transmit sound better than thicker double-glazed and laminated options. Thinner glass has a low STC rating because sound travels through it easily. The higher the STC rating, the more sound will be dampened. Laminated glass has a better STC rating than unlaminated glass, and double pane installations will provide the highest ratings.

Sound Transmission Class ratings

When planning glass wall systems, here’s a rough guide to how well each STC rating will block sound:

·   25 – you can hear talking through the glass

·   30 – you can hear speaking but it’s muffled, and you may not understand words

·   35 – you can hear loud speaking, but not normal speech

·   40 – you can hear loud speech but may not understand words

·   45 – you hear loud speech but can’t make out words

·   50 – it’s difficult to hear even loud speech

·   55 – loud shouting may be audible if straining to hear it

The STC rating of a glass wall is determined by the system configuration. Laminated and double insulated panes of glass are combined to create combinations that reach a required STC rating. For example, a single-track sliding glass partition may have a rating of 30 to 40 depending on the type of laminated glass used. For more sound dampening, double insulated laminated glass systems can have STC ratings of 45 or more.

Our installation experts help you create glass wall systems that meet or exceed the sound dampening requirements of your facility. From office buildings to health care facilities, we have installed hundreds of glass wall systems and enclosures, and we can do the same for you. Contact us for a consultation and get the right STC rated system for your next project.

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