18 ACOUSTIC PRIVACY 4.5” (114 mm) daylight-friendly double-glazed channel glass walls provide outstanding acoustic benefits. Our silicone-sealed interlocking channel glass systems without insulation are projected to deliver STC 38. With added insulation inserts, the systems can deliver STC up to 43 (for interior walls) and OITC up to 36 (for exterior walls). Note that STC 40 is considered the “onset of acoustic privacy” (speech becomes inaudible through the wall). In comparison, Sheetrock-clad interior stud walls of the same thickness offer lower STC 33 without insulation and STC 39 with fiberglass insulation; they are also completely opaque to light. Bendheim’s double-glazed channel glass with insulation Daylight-friendly wall No daylight Typical stud & sheetrock wall with insulation Bendheim’s double-glazed channel glass Typical stud & sheetrock wall STC Rating 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 24 35 36 37 38 39 40 41 42 43 Little or no acoustic “privacy” Loud speech can still be understood Speech becomes unintelligible Onset of “privacy”