Tests
6
Effect of Insulation Flow Resistivity
Rw range
9–25dB
spread 16 dB
Highest Rw
25dB
GW 90 mm R2.7 (34,000 N·s/m⁴)
Largest ΔRw vs first
+17dB
GW 90 mm R2.7 (34,000 N·s/m⁴)
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 | Project025 | 9 | 0 | 0 | ref. | +8 | 9.1 | |
| GW 100 mm R5 (8,800 N·s/m⁴) | Project028 | 18 | −1 | −3 | +9 | +17 | 15.6 | |
| GW 175 mm R3.5 (9,500 N·s/m⁴) | Project030 | 20 | −1 | −3 | +11 | +19 | 17.4 | |
| GW 45 mm R2.5 (12,000 N·s/m⁴) | Project026 | 15 | 0 | −1 | +7 | +15 | 13.9 | |
| GW 90 mm R2.5 (15,000 N·s/m⁴) | Project027 | 20 | 0 | −2 | +12 | +20 | 18.4 | |
| GW 90 mm R2.7 (34,000 N·s/m⁴) | Project029 | 25 | 0 | −3 | +17 | +25 | 24.2 |
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.