Worked Example: Hotel Bedroom — BS 8233 Sleep Quality Design
50 m³ hotel room with heavy carpet, full-height curtains, and upholstered headboard
A 50 m³ residential living designed to BS-8233 requires RT60 ≤ 0.6s. With Painted plaster on the ceiling, the calculated RT60 is 0.51s — PASS.
Room Setup
Total surface area: 86.2 m². Calculation method: Sabine equation (ISO 3382-2:2008 Annex A).
Surface Materials
| Surface | Material | Area (m²) | NRC |
|---|---|---|---|
| Ceiling | Painted plaster | 20.0 | 0.04 |
| Floor | Heavy carpet | 20.0 | 0.29 |
| Walls — plasterboard | Plasterboard on studs | 28.0 | 0.07 |
| Curtains (full-height) | Curtains (medium weight) | 6.0 | 0.56 |
| Bed + soft furnishings | Upholstered seating | 5.0 | 0.55 |
| Window | Double glazing 6mm | 4.0 | 0.03 |
| Doors (bath + entry) | Solid timber door | 3.2 | 0.09 |
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 = 5 × 4 × 2.5 = 50 m³
- 2
Total Surface Area
Stotal = 20.0 + 20.0 + 28.0 + 6.0 + 5.0 + 4.0 + 3.2 = 86.2 m²
- 3
Absorption per Surface at 500 Hz
Ceiling: 20.0 m² × 0.04 = 0.80 Sabins
Floor: 20.0 m² × 0.14 = 2.80 Sabins
Walls — plasterboard: 28.0 m² × 0.05 = 1.40 Sabins
Curtains (full-height): 6.0 m² × 0.49 = 2.94 Sabins
Bed + soft furnishings: 5.0 m² × 0.56 = 2.80 Sabins
Window: 4.0 m² × 0.04 = 0.16 Sabins
Doors (bath + entry): 3.2 m² × 0.08 = 0.26 Sabins
- 4
Total Absorption at 500 Hz
Atotal = 0.80 + 2.80 + 1.40 + 2.94 + 2.80 + 0.16 + 0.26 = 11.16 Sabins
- 5
Sabine RT60 at 500 Hz
RT60 = 0.161 × V / A = 0.161 × 50 / 11.16 = 0.72s
- 6
Compare to Target
Mid-frequency RT60 (avg of 500, 1k, 2k Hz) = 0.51s. Target: 0.3--0.6s per BS-8233. Verdict: PASS
Octave Band Results
| Frequency | 125Hz | 250Hz | 500Hz | 1kHz | 2kHz | 4kHz |
|---|---|---|---|---|---|---|
| Total Absorption (Sabins) | 11.1 | 8.6 | 11.2 | 17.8 | 22.6 | 23.4 |
| RT60 (s) | 0.72 | 0.93 | 0.72 | 0.45 | 0.36 | 0.34 |
| Target (s) | — | — | 0.60 | 0.60 | 0.60 | — |
| Verdict | — | — | FAIL | PASS | PASS | — |
Compliance Verdict
Reference:
Open the AcousPlan calculator pre-loaded with the exact room dimensions (5m × 4m × 2.5m) and RT60 target (0.6s).
Open CalculatorField Story
A boutique hotel group opening a 96-room property near London Bridge station faces the challenge of delivering 4-star sleep quality adjacent to a major railway. Each 5 m by 4 m guest room uses heavy wool carpet, full-height blackout curtains with acoustic lining, and an upholstered headboard wall to absorb speech and television reflections. Plasterboard on independent stud walls — decoupled from the structural frame — provides both Part E sound insulation and panel absorption at low frequencies. BS 8233:2014 specifies indoor ambient noise levels of 30 dB LAeq,T for bedrooms and recommends short reverberation times to prevent amplification of intrusive noise. The calculation demonstrates that even without an acoustic ceiling tile, the combination of soft furnishings in a small room achieves adequate absorption for comfortable sleeping conditions.
Frequently Asked Questions
What RT60 does a Hotel Bedroom — BS 8233 Sleep Quality Design achieve?
With the specified materials and dimensions (5m x 4m x 2.5m, volume 50m3), the calculated mid-frequency RT60 is 0.51s using the Sabine equation. The target under BS-8233 is 0.3--0.6s. The result is a PASS.
What materials are used in this hospitality acoustic example?
This example uses Painted plaster on the Ceiling (NRC 0.04), Heavy carpet on the Floor (NRC 0.29), Plasterboard on studs on the Walls — plasterboard (NRC 0.07), Curtains (medium weight) on the Curtains (full-height) (NRC 0.56), Upholstered seating on the Bed + soft furnishings (NRC 0.55), Double glazing 6mm on the Window (NRC 0.03), Solid timber door on the Doors (bath + entry) (NRC 0.09). The total absorption at 500 Hz is 11.2 Sabins.
How much does acoustic treatment cost for this room?
Cost data is not available for this example. Use the AcousPlan calculator to estimate treatment costs for your specific room configuration.
Related Examples
Restaurant Dining Room — BS 8233 Acoustic Design
Hotel Lobby — ASHRAE RC 35-40 Design
Care Home Lounge — Elderly Hearing-Optimised
Hotel Corridor — BS 8233 Flanking Noise Control
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.