Tests
2
Effect of Insulation
Rw range
23–34dB
spread 11 dB
Highest Rw
34dB
GW 90 mm R2.7
Largest ΔRw vs first
+15dB
GW 90 mm R2.7
Sound reduction index
R′ from the 2270, re-referenced to the 0.9216 m² specimen area (−0.35 dB). Grey lines: reference bounds.
Single-number ratings
Open in explorer| Varies | Test | Rw | C | Ctr | ΔRw vs first | ΔRw vs open | Mean R | |
|---|---|---|---|---|---|---|---|---|
| No Insulation | Project069 | 23 | −1 | −1 | ref. | +23 | 20.8 | |
| GW 90 mm R2.7 | Project070 | 34 | −2 | −6 | +15 | +33 | 32.0 |
Rw, C and Ctr per ISO 717-1 over 100–3150 Hz. ΔRw fits the reference curve to the band-by-band difference curve, which is not the same number as subtracting two separately rounded Rw values. Mean R is the arithmetic mean over the 16 rating bands.