For all your Window, Door & Security Solutions.

What is the difference between STC and Rw ratings?

STC & Rw are laboratory test results and both mean the same as they relate to measuring sound, and are the terms used for acoustic ratings.

The STC abbreviation means Sound Transmission Class, it is the measurement of internal sound transmission, eg high frequencies. The number rating that is used to determine how much a material, eg glass window will resist sound travelling through the air (airborne sound transfer).

Rw abbreviation means weighted sound reduction index which uses airborne sound and is a scientific calculation, this is better for rating the attenuation of external low frequency noise, eg outside traffic travelling through a material, eg glass window.

This means a commercial window could have a STC rating of 30 but can be rated as 25 dB (decibel) for noise.

Posted in: General FAQs

Showroom Opening Hours:

8:30am - 4:00pm 8:30am - 4:00pm 8:30am - 4:00pm 8:30am - 4:00pm 8:30am - 4:00pm
Map_Icon View Showroom Location.

Values & Commitments

CDK are proud of our highly skilled workforce, exemplified by a number of our staff whose families have worked for us through the generations.

Our workforce is further complimented by our specialist sub-contractors who we have known and worked with for many years.

Bushfire Attack Levels

In the Australian Standards As 3959, they have classified different bushfire intensity levels that a home may experience during a bushfire.

These are referred to as Bushfire Attack Levels, or BAL’s for short.

Read More
1/55 Cameron Street,
Cranbourne, Victoria,
Australia, 3977
03 5996 3069
03 5996 3070