Acoustic louvres and plenums are specialised products that combine visual openness with acoustic protection on façade openings (generator air intakes, mechanical room vents). Horizontal blade construction lets air through while deflecting sound waves; the rear plenum volume adds further absorption. Typical attenuation: 15-25 dB.
What is an acoustic louvre?
An acoustic louvre is a façade-grille product made up of horizontal blades — visually similar to a standard louvre but with sound-absorbent fill inside the blade profile. It allows airflow while breaking the direct line-of-sight transmission path of sound waves.
What is a plenum?
A plenum is the absorbent-lined volume behind the acoustic louvre. As airflow makes a labyrinth path through the plenum, the sound wave loses energy in the absorber. The louvre + plenum combination delivers 2-3× the attenuation of a louvre alone.
Where are they used?
- Generator air intake openings (façade)
- External ventilation of mechanical rooms
- Transformer-substation cooling air
- Car park / garage ventilation
- Industrial exhaust air systems
- Cooling-tower perimeter ventilation
System components
- Acoustic blade louvre: horizontal V or Z profile with absorbent fill
- Plenum volume: 600-1500 mm deep chamber behind the louvre
- Plenum interior absorbers: sound-absorbent panels on every face
- Airflow control: rain and pest protection
- Fire damper: as required by fire code
Performance calculation
An acoustic louvre alone delivers 8-15 dB; with a plenum it rises to 18-28 dB. In our practice we use the louvre + plenum combination on every generator project.
Target performance
- Louvre alone: 8-15 dB
- Louvre + plenum: 18-28 dB
- Airflow: design capacity preserved
- Pressure drop: <30 Pa
Weather resistance
As a façade product the acoustic louvre is built from weather-resistant materials: galvanised steel or aluminium body, stainless fasteners and integrated water drainage.
Time and cost
Per façade opening 1-3 weeks. Investment scales with opening size and target attenuation.
Certification
EN ISO 7235 (silencer), EN 13501-1 (fire), EN 13030 (façade-louvre durability) certified.
Features
On-site acoustic measurement and noise source analysis
Detailed engineering with professional simulation software
Certified material selection (BS476 Class 0, UNI 9175)
Meticulous installation and execution with our experienced team
Final measurement and performance warranty report
Process
Survey & Measurement
On-site survey and acoustic measurement.
Simulation & Design
Simulation with acoustic software, detailed quote.
Installation
Turnkey installation with certified materials.
Verification & Report
Final measurement, performance report, warranty.
Technical Specifications
| Application Standard | BS476 Class 0, UNI 9175 M1, Firex |
|---|---|
| Typical Noise Reduction | 25-45 dB (project-dependent) |
| Installation Time | Confirmed after survey (1-15 days) |
| Warranty | Measured result + 2-year workmanship warranty |