How we design our Louvre system projects

Louvres serve a variety of purposes in modern buildings, from providing shelter and ventilation for key mechanical equipment, to offering privacy or a memorable aesthetic feature in a façade. Whilst louvres are based on centuries old technology, modern solutions can be highly customised to meet the specific requirements of a project, including everything from the level of air flow and noise transmission, to the final colour and finish.

In this article, we look at some of the key considerations for louvres, and how our louvre team can develop a tailored design which delivers for your project.

What we offer in a louvre project

Colt can support you at each step, from developing the initial louvre design and specification, to manufacture at our UK facility and installation by our experienced sub-contractors. The process is overseen by our dedicated louvre team who together have decades of experience project managing the delivery of louvres across a wide range of projects. This ensures that the solution will meet your requirements and is backed with expert technical support. 

The key considerations within a louvre project

There are a number of factors which need to be considered when designing a louvre for a project. Often, achieving the optimal design will mean carefully balancing these different elements.

Airflow

Perhaps the most obvious performance consideration when selecting a louvre is how well it can help to ventilate the internal space.

In the past a common metric used to assess this was the “free area”. This is the open area on the louvre through which air can flow expressed as a percentage. In practice, however, this metric can be misleading as it doesn’t consider a number of factors which are critical to how well air is able to flow through the louvre, such as the shape and angle of the blades.

For this reason, when considering airflow in our designs we focus on the aerodynamic efficiency (Cv) – the higher this value, the more efficient the louvre will be. A louvre with a high Cv can achieve a lower pressure drop for the same airflow and louvre panel size as a less aerodynamic model – improving ventilation levels. The aerodynamic efficiency of louvres is considered in HEVAC 4th Edition test standard which uses a straightforward classification system.

Weather proofing

All external louvres need to provide some level of protection against the elements. How much protection is required will depend on a variety of factors including the location of the building, where on the building the louvre is situated (roof-top locations will typically be exposed to greater wind-driven rain than lower-level applications) and what is contained within the internal space it is protecting.

The rain defence performance of louvres is assessed under BS EN 13030:2001 and louvres are categorised from Class A (best) to Class D (worst). As part of the test, louvres are assessed at a range of different face velocities and may be classified at different levels for different velocities.

In most cases, where additional rain defence is required, we recommend our two or three banked louvre options.

Noise

In some cases, limiting the noise transmission through the louvre can be preferable or a planning requirement due to local noise restrictions.

The acoustic performance of louvres is assessed based on their weighted sound reduction index (Rw) – this is their ability to limit airborne noise and is assessed under BS EN ISO 10140-2:2021. A higher Rw value indicates the unit will limit noise more effectively. Two further correction values may also be provided - C and Ctr. These adjust the Rw value based on performance with mid-frequency noise (C) and low-frequency noise (Ctr).

Our CALM Acoustic Louvre Modules provide excellent acoustic performance. Depending on the project requirements, these can be supplied with either straight or chevron blades.

The chevron blades lengthen the path that sound waves need to travel to pass through the module and to help deflect them. This means they can deliver enhanced acoustic performance — particularly at mid to high frequencies — whilst maintaining effective airflow.

Aesthetics

In addition to ensuring louvres meet the performance requirements on a project, it is also important that they fit into the overall aesthetic of the building. We can design and manufacture louvres in both vertical and horizontal arrangements in a wide range of sizes and depths to suit your project.

Each louvre can be powder-coated in any RAL colour or completed with specialist marine-grade coatings for high corrosion environments. This helps to ensure they will look their best for years to come. 

Ancillaries

We can also supply our louvres with a range of ancillaries depending on the project requirements. These can include panel kits, which enable the construction of large assemblies without excessive support structures, and vermin and insect screens in a range of different configurations.

Our technical services

Colt offers a leading design and technical service which covers our full range of climate control, natural ventilation, solar shading, and smoke ventilation systems. Using the latest modelling software, our team can develop a bespoke specification for your project which can include not only highly optimised louvre designs, but also any integrations with wider mechanical and smoke ventilation systems.

Our customisable louvre range

We offer a range of louvre solutions which are available in a range of sizes, finishes and customisation options to meet your project requirements.

• Screening Louvre (1UL) – featuring a single banked design with 50 and 100 mm blade pitches, this louvre provides a simple, stylish solution for screening and cladding applications.
• Ventilation Louvre (2UL) – with a double banked design, this louvre provides excellent airflow and rain defence.
• Weather Louvre (3UL) – our 3UL louvre delivers proven performance in some of the most demanding applications. Its triple banked design provides excellent rain defence whilst still supporting effective ventilation.
• Colt Acoustic Louvre Modules (CALM) – these panels feature cutting-edge noise reduction technology, helping to limit sound transmission in applications where strict noise limits apply. CALM modules are designed to seamlessly integrate with our Universal louvre range.