DOORGLASS & ENCLOSED BLINDS

Sound Transmission Class (STC)



Definition


STC is expressed in decibels (dB) and is used to measure a building material's ability to reduce sound. A higher STC rating translates into more reduction in sound. Laboratory testing is used to measure the resistance of partitions such as walls, windows, or entry doors to the passage of sound.

The material with the lowest resistance to the passage of sound limits a partition's STC value. Poor construction practices can also nullify a partition's sound reduction properties. Cracks due to improperly fitted doors or windows can be a prime source of sound leakage.


STC Values


ODL conducted third party IAS-accredited lab testing on a range of doorglass configurations. All of the doorglass samples were 22" x 64" except the sliding patio door blind which was 33" x 74". These sound transmission loss tests were conducted in accordance with ASTM E 90. The Sound Transmission Class (STC) rating was calculated in accordance with ASTM E 413. Test results and benchmark values are presented below.
Family Configuration STC Comment
Deco Decorative glass with caming 31 Third party tested
(1.39 M) Adobe PDF
1-lights,
grilles
between
glass,
external
grilles
1/2" IG, clear glass 1-light,
1/4" air space, Intercept® spacer
26 Third party tested
(1.39 M) Adobe PDF
1/2" IG, clear glass, external grille,
1/4" air space, Intercept® spacer
26 Third party tested
(1.39 M) Adobe PDF
1" IG, clear glass 1-light,
3/4" air space, Intercept® spacer
28 Third party tested
(1.39 M) Adobe PDF
1" IG, clear glass, grilles between glass,
3/4" air space, Intercept® spacer
30 Third party tested
(1.39 M) Adobe PDF
Simulated divided light,
grilles between glass with external grilles,
3/4" air space, Intercept® spacer
30 Third party tested
(1.39 M) Adobe PDF
Sound Suppression 1" IG 1-light with laminated glass 34

Third party tested
(183 K) Adobe PDF

Blinds Triple-glazed, grilles between glass blind,
with Intercept® spacer,
slats lowered and closed
34 Third party tested
(394 K) Adobe PDF
Dual-glazed blind, with Intercept® spacer,
slats lowered and closed
32 Third party tested
(394 K) Adobe PDF
Sliding patio door blind,
Intercept® spacer,
slats lowered and closed
28 Third party tested
(394 K) Adobe PDF
Door and
window
reference
information
3' x 7' steel door,
1-3/4" thick with polyurethane core
26 From HUD Noise
Notebook*
30" x 48" aluminum clad
casement window,
1" IG with 1/8" panels
29 From HUD Noise
Notebook*

 

* Source: HUD Noise Notebook chapter 4 supplement, Sound Transmission Class guidance