Worked Example: Conference Room — DIN 18041 Acoustic Design
RT60 calculation for a 12-person conference room in a German office building under DIN 18041. Perforated timber slat ceiling provides warm aesthetics with good acoustic performance, complemented by carpet flooring.
A 144 m³ meeting room designed to DIN-18041 requires RT60 ≤ 0.7s. With Perforated timber slats on the ceiling, the calculated RT60 is 0.43s — PASS.
Room Setup
Total surface area: 192.6 m². Calculation method: Sabine equation (ISO 3382-2:2008 Annex A).
Surface Materials
| Surface | Material | Area (m²) | NRC |
|---|---|---|---|
| ceiling | Perforated timber slats | 48.0 | 0.65 |
| walls-main | Painted plaster | 84.0 | 0.04 |
| floor | Carpet (heavy) | 48.0 | 0.30 |
| windows | Double glazing 6mm | 9.0 | 0.04 |
| door | Solid timber door | 3.6 | 0.08 |
Absorption coefficients sourced from manufacturer datasheets and ISO 354 test reports. Browse the full acoustic materials database.
Step-by-Step Calculation
- 1
Room Volume
V = L × W × H = 8 × 6 × 3 = 144 m³
- 2
Total Surface Area
Stotal = 48.0 + 84.0 + 48.0 + 9.0 + 3.6 = 192.6 m²
- 3
Absorption per Surface at 500 Hz
ceiling: 48.0 m² × 0.70 = 33.60 Sabins
walls-main: 84.0 m² × 0.04 = 3.36 Sabins
floor: 48.0 m² × 0.14 = 6.72 Sabins
windows: 9.0 m² × 0.04 = 0.36 Sabins
door: 3.6 m² × 0.08 = 0.29 Sabins
- 4
Total Absorption at 500 Hz
Atotal = 33.60 + 3.36 + 6.72 + 0.36 + 0.29 = 44.33 Sabins
- 5
Sabine RT60 at 500 Hz
RT60 = 0.161 × V / A = 0.161 × 144 / 44.33 = 0.52s
- 6
Compare to Target
Mid-frequency RT60 (avg of 500, 1k, 2k Hz) = 0.43s. Target: 0.4--0.7s per DIN-18041. Verdict: PASS
Octave Band Results
| Frequency | 125Hz | 250Hz | 500Hz | 1kHz | 2kHz | 4kHz |
|---|---|---|---|---|---|---|
| Total Absorption (Sabins) | 13.3 | 29.4 | 44.3 | 58.5 | 64.7 | 62.3 |
| RT60 (s) | 1.75 | 0.79 | 0.52 | 0.40 | 0.36 | 0.37 |
| Target (s) | — | — | 0.70 | 0.70 | 0.70 | — |
| Verdict | — | — | PASS | PASS | FAIL | — |
Compliance Verdict
Reference: DIN 18041:2016 Table 1
DIN 18041 Group A classification for conference rooms requires RT60 of 0.4-0.7s. The perforated timber ceiling provides both diffusion and absorption, creating a natural warm sound suited to extended discussions.
STI result: 0.74 (per IEC 60268-16:2020)
Cost Estimate
Costs are indicative and vary by region, supplier, and installation complexity. For a detailed cost breakdown, use the AcousPlan calculator.
Open the AcousPlan calculator pre-loaded with the exact room dimensions (8m × 6m × 3m) and RT60 target (0.7s).
Open CalculatorField Story
A Stuttgart engineering firm's conference room is used for 6-hour client workshops where participants must discuss technical drawings in detail. The original room with its plaster ceiling and walls produces an RT60 of 1.1 seconds, causing listener fatigue during long sessions. Participants report feeling exhausted after meetings. The interior architect proposes perforated oak slats with mineral wool backing on the ceiling, creating a warm Swabian aesthetic that the firm's clients associate with quality engineering. Combined with heavy carpet, the room achieves DIN compliance without any visible acoustic panels on the walls.
Frequently Asked Questions
What RT60 does a Conference Room — DIN 18041 Acoustic Design achieve?
With the specified materials and dimensions (8m x 6m x 3m, volume 144m3), the calculated mid-frequency RT60 is 0.43s using the Sabine equation. The target under DIN-18041 is 0.4--0.7s. The result is a PASS.
What materials are used in this office acoustic example?
This example uses Perforated timber slats on the ceiling (NRC 0.65), Painted plaster on the walls-main (NRC 0.04), Carpet (heavy) on the floor (NRC 0.3), Double glazing 6mm on the windows (NRC 0.04), Solid timber door on the door (NRC 0.08). The total absorption at 500 Hz is 44.3 Sabins.
How much does acoustic treatment cost for this room?
The estimated treatment cost is €6,912 for 96 m2 of absorptive material at approximately €72/m2. Actual costs vary by region, supplier, and installation complexity.
Related Examples
Open Plan Office — BS 8233 Acoustic Design
Small Meeting Room — BS 8233 Acoustic Design
University Tutorial Room — WELL F74 Compliance
Executive Boardroom — WELL F74 Premium Finish
Explore More
All calculations are advisory and based on the Sabine equation (ISO 3382-2:2008 Annex A). Results require professional verification for compliance submissions. Absorption coefficients are sourced from manufacturer datasheets and ISO 354 test reports.