What factors need to be considered when specifying acoustic louvres?
Specifying acoustic louvres requires a careful balance between sound attenuation, airflow efficiency, weather performance, and architectural integration.
Topics covered:
- How required acoustic performance affects specification.
- The influence of building use on acoustic requirements
- Impact of free area on airflow and sound performance
- Balancing weather resistance with acoustic performance
- Aesthetic integration of acoustic louvres.
Every project brings its own requirements, but a successful acoustic louvre specification is guided by a set of core criteria: acoustic performance, airflow performance, resistance to weather and rain penetration, site conditions, internal building use, and aesthetic integration.
Acoustic Performance
Selecting the right acoustic louvre begins with defining the acoustic requirement. This includes identifying the target sound reduction levels, expressed in Rw (Weighted Sound Reduction) or SRI (Sound Reduction Index) values, based on planning constraints, environmental noise levels, or internal comfort expectations. Higher performance often requires deeper louvre profiles or double-bank configurations, so collaboration with an acoustic consultant is key to ensuring the required reduction is achieved.
Building Function
The building’s purpose shapes acoustic needs and system selection. Residential projects focus on occupant comfort; data centres prioritise noise control and maximum airflow; healthcare facilities require acoustic and ventilation considerations, whereas commercial buildings often need a blend of sound control, weather resistance, and visual screening.
Airflow and Pressure Drop
Another fundamental consideration is airflow efficiency. Acoustic louvres, due to their internal baffles, typically offer a lower free area than standard ventilation louvres. This reduction in free area results in a higher pressure drop, which can affect fan effectiveness and increase energy usage. Reviewing data on pressure drop versus airflow curves is essential to ensure that the system is correctly sized and that ventilation targets are achievable without compromising acoustic performance.
Weather Protection
Environmental exposure also plays a role in product selection. While many acoustic louvres are designed to provide weather protection and achieve a Class A rain defence rating, this level of performance may not be necessary in all applications. In covered plant areas or sheltered installations, louvres with moderate weather resistance and superior sound attenuation may offer a better overall balance. Specifying a higher level of rain defence than needed can lead to higher fan energy requirements and increased long-term operational costs, so the actual exposure level and acoustic requirements should guide the decision.
Aesthetic Integration
As acoustic louvres often form a visible part of the façade or rooftop plant area, their integration into the architectural aesthetic is another important aspect of specification. Blade profiles, frame depths, colours, and finishes can be selected to complement or match the building’s design language. In situations where both screening and noise control are needed, such as around HVAC units or generators, acoustic louvres can serve dual purposes, providing both visual concealment and high-performance sound attenuation.