In the age of open floor plans and chiming cell phones, silence is golden. That may explain the growing demand by architects and building owners for sound resistant doors.
Acoustic doors are engineered to prevent a specific amount of sound from passing through a door. They have been common in loud environments such as manufacturing facilities and music studios for decades, but they have become increasingly popular in office buildings, hotels, and schools too.
A door’s Sound Transmission Class (STC) rating specifies how much sound is prevented from passing through the door. The higher the STC rating, the more sound resistant the door.
| STC | What can be heard |
|---|---|
| 25 | Normal speech can be understood easily and distinctly |
| 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 |
| 50 | Very loud sounds such as musical instruments or a stereo can be faintly heard |
| 60+ | Superior soundproofing; most sounds inaudible |
Resources
Manufacturers usually have proprietary cores for their acoustic doors. It’s important to specify to the performance rather than the core material because that’s what matters. It could be to an STC or OITC value, or even the performance at specific frequencies.
The acoustic door manufacturers below have been audited to meet SDI standards.
