Renson Louvres: What Contractors Need to Know Before Ordering
July 27, 2026
Ventilation openings are essential in many buildings, but they can also create a direct path for noise.
That noise may be coming from mechanical equipment inside the building, such as fans, generators, cooling systems or air handling units. In other cases, the concern is noise entering from outside, particularly on sites close to busy roads, railways or industrial areas.
Closing the opening is rarely an option because air still needs to move through the building. A standard weather louvre may be suitable where ventilation and rain resistance are the main concerns. Once noise also needs to be controlled, the opening requires a louvre with measured acoustic performance.
Renson acoustic louvres are made for this type of application. They allow air to pass while reducing the amount of sound travelling through the opening.
As the exclusive fabricators of Renson louvres in Ireland, CS Fabrication manufactures genuine Renson systems at our Dublin facility for commercial, residential and industrial projects across the country.
What Makes an Acoustic Louvre Different?
From the outside, an acoustic louvre may look similar to a conventional blade system. The important difference sits inside the blades.
Renson acoustic louvres combine aluminium profiles with non flammable mineral wool. This material absorbs part of the sound energy travelling through the opening, while the blade arrangement leaves enough space for air to pass. Stainless steel mesh also forms part of the standard construction.
An acoustic louvre does not turn a ventilation opening into a solid wall, and it cannot guarantee silence on either side. Its purpose is to provide a measurable reduction in sound transmission where the opening still needs to remain ventilated.
That distinction matters because different types of noise behave differently. A constant fan hum will not have the same sound characteristics as a generator, cooling unit, road traffic or passing trains.
The louvre therefore needs to be considered in relation to the noise involved rather than treated as a general soundproofing product.
Why Independent Testing Matters
The word acoustic can easily appear in a product description without giving any clear indication of how much sound reduction the product actually provides.
That is not enough where a project has a planning condition, a boundary noise limit or a specific requirement from an acoustic consultant. Architects and engineers need figures they can assess against the proposed use of the building.
The six Renson acoustic louvre types have been independently tested. Peutz carried out the acoustic testing under EN ISO 10140 and EN ISO 717 1, while BSRIA testing covers airflow and water resistance under EN 13030.
This gives the project team useful information including:
- Weighted sound reduction, shown as Rw
- Sound reduction at different frequencies
- Airflow resistance
- Physical free area
- Water resistance
- Louvre depth and minimum dimensions
Instead of relying on a general claim about noise reduction, the design team can compare actual performance before a profile is selected.
What Does the Rw Figure Tell You?
Rw is a single figure used to express the overall airborne sound insulation of a tested building element.
In simple terms, a higher Rw rating means greater overall sound reduction under laboratory conditions. It does not mean that every frequency will be reduced by exactly the same number of decibels.
That is why a louvre should not be chosen simply because it has the highest Rw number.
The type of noise being produced, where that noise is being received and the reduction required all need to be considered before the final profile is chosen.
Six Renson Acoustic Louvre Options
The current Renson range includes six acoustic profiles, giving project teams several levels of noise reduction and different installation depths:
Renson 445/86
Renson 448/150
Renson 448/225
Renson 448/300
Renson 449/150
Renson 449/225
The model with the highest acoustic rating will not suit every building.
A deeper louvre needs more room within the wall and may affect the ventilation design. Where the acoustic requirement is lower, a shallower option may make more sense.
The right choice comes from balancing the sound reduction needed with airflow, available space and the surrounding construction.
Acoustic Performance, Airflow and Wall Depth Need to Work Together
Three questions usually shape the choice of acoustic louvre. How much sound needs to be reduced? How much air must pass through the opening? How much space is available within the wall?
Looking at any one of these on its own can cause problems later.
The size of the opening alone does not tell you how much air the finished louvre can handle. Frames, blades, mesh and acoustic material all affect the route through the opening.
Before the louvre size is finalised, the mechanical design should confirm the required airflow volume, whether the opening is being used for intake or discharge and the acceptable pressure loss.
This is important for all plant room louvres, but acoustic profiles can require additional depth and need closer coordination with the wall construction.
That depth can affect duct connections, support steel, insulation, flashings and the space available around nearby equipment.
Smaller openings also need particular care. A louvre may provide the required acoustic performance but still be unsuitable for the dimensions shown on the drawings.
Our guide to ordering Renson louvres covers the opening dimensions, frame sizes, wall build ups and other project information that should be agreed before manufacture begins.
Where Can Acoustic Louvres Be Used?
Acoustic louvres are useful anywhere ventilation is needed but allowing noise to pass freely through the opening would create a problem.
A rooftop plant room beside an apartment development is one obvious example. The equipment needs air, while nearby residents need protection from unnecessary mechanical noise.
The same issue can arise around generators, cooling equipment, air handling units, data centre plant areas and energy centres. Large ventilation openings may be essential, but leaving them acoustically untreated can give sound a clear route out of the building.
Ventilated car parks are another common application. These spaces need substantial airflow, yet they may sit close to homes, offices or public areas where noise needs to be controlled.
Acoustic louvres can also help where the concern comes from outside the building. A residential or commercial property close to a busy road, railway line or industrial site may need ventilation without allowing as much external noise to enter.
Typical applications include:
- Plant rooms close to homes or offices
- Generator and cooling equipment enclosures
- Data centres and energy centres
- Ventilated car parks
- Industrial buildings
- Residential and commercial façades close to busy roads or railway lines
The requirement will be different for every site. The noise source, the location being protected and the ventilation duty all need to be considered together.
Weather Performance Still Matters
Adding acoustic performance does not remove the need to deal with rain and exposure.
Every Renson acoustic profile has tested water resistance performance under EN 13030. The result varies between models and operating conditions, so weather resistance should form part of the selection process.
Options can include a drainage blade, water channel and frame arrangements with or without a flange. Different mesh configurations may also be used depending on the project.
The louvre itself is still only one part of the external wall. The completed detail needs suitable flashings, cills, drainage routes and perimeter seals, particularly where sensitive equipment sits behind the opening.
The surrounding construction also matters acoustically. A gap around the frame or an untreated connection behind the louvre can give sound another way through the wall.
That means the louvre and the surrounding wall detail need to work together.
The Louvre Still Has to Suit the Façade
Noise reduction may be the main reason for choosing an acoustic louvre, but the finished unit remains part of the building elevation.
Blade alignment, frame position and joint locations deserve the same attention given to larger external louvre screens. Where several units appear across one elevation, consistent blade lines can make a noticeable difference to the finished appearance.
Renson acoustic louvres are available with a range of architectural finishes, including anodised aluminium and powder coated options.
CS Fabrication completes powder coating in house, allowing louvre frames, blades and associated aluminium components to be finished as part of the same package. A wide selection of RAL colours and matt, gloss, satin or textured finishes is available.
Renson Acoustic Louvres Fabricated in Ireland
As the exclusive fabricators of Renson louvres in Ireland, we provide a local manufacturing route for genuine Renson systems.
Renson profiles and subframes are supplied to our Dublin manufacturing facility, where the louvres are fabricated and powder coated to the approved project information. Fabrication, finishing and quality checks can all be coordinated locally before delivery.
For an acoustic louvre package, we need accurate opening dimensions, finish details and information about any mesh, drainage or flange options. Where a Renson profile has already been specified, this should also be included with the project drawings. The airflow requirements and required acoustic performance should be confirmed by the relevant members of the design team.
We can then review the specified profile against the latest drawings and finalise the details needed for manufacture. If a profile has not yet been chosen, the acoustic and mechanical requirements should be agreed first so the available Renson options can be compared properly.
Planning a Project with Renson Acoustic Louvres?
Choosing an acoustic louvre is about finding the right balance. The system needs to reduce noise, provide enough air, cope with the building's exposure and fit properly within the wall.
Independent testing gives the project team reliable performance information to assess before the louvre reaches fabrication.
Send us your latest drawings, louvre schedule and available acoustic and mechanical information. We can review the proposed Renson system, identify any fabrication details that still need to be resolved and provide pricing for the agreed package.
Call 01 912 5324 or submit your project information through our quotation form.
