How Ventilated Cladding works
Ventilated cladding systems are an effective way of protecting the building envelope from the elements whilst improving their thermal efficiency, fire and acoustic protection and extending the life of the building.
The concept of a double-leaf structure first appeared in Scandinavia in the 1950s. Known as the ‘open joint barn technique’, it was used to construct timber barns to reduce moisture damage to stored hay and grain by encouraging natural ventilation.
Today’s sophisticated vented systems work on similar principles. They consist of an outer protective rainscreen barrier attached to an inner well-insulated load-bearing wall with a cavity in-between.
The key is the air gap which acts just like a chimney stack.
How the stack effect works in ventilated façades
The vented cladding system is built around rising warm air creating an upward draft that pulls in cooler air from below. This is known as the ‘stack effect.’
This constant upward air movement carries away any moisture from inside the cavity and any condensation that could potentially lead to a build-up of mould or mildew or the degradation of the existing structure. Any water that enters through the open top will just run down the inside of the decorative panels and drain away at the base of the wall.
The air gap also acts as additional insulation slowing down heat transfer from the outside the building. In the summer the updraught of air helps dissipate the heat and in the winter, the cold air trapped within the cavity slows down heat loss from inside the building.
The benefits of open joints in vented façades
A key feature of ventilated wall cladding is its open joints. Instead of bonding the outer rainscreen panels tightly together, which could result in condensation building up, an air gap of 8-12mm is left open.
An additional, but significant benefit is that the pressure of the wind blowing against the front of a ventilated façade can further boost air circulation and the evaporation of any moisture within the cavity.
As a practical safeguard of the integrity of the outer structure, the small open joints also prevent excessive wind load on the surface of the building, whilst allowing for some thermal movement or expansion.
How Equitone adds value to ventilated cladding
Fundamental to the effectiveness of a ventilated cladding system is the choice of material.
Although there is a wide range of options from aluminium and stainless steel to terracotta and natural stone, we believe that EQUITONE’s fibre cement cladding is the most technically suitable.
• Thermal performance
Thermal properties of cladding can impact the overall performance of the system. Whereas some materials like metal transfer heat more easily, EQUITONE’s fibre cement cladding has much lower conductivity.
• Weight
The weight of cladding can put unnecessary stress on a structure. Unlike terracotta and natural stone, EQUITONE’s fibre cement cladding is lightweight and therefore more versatile and suitable for a wider range of projects.
• Durability
Different materials require different levels of maintenance. EQUITONE’s fibre cement cladding can withstand harsh weather like rain, snow, and UV rays ensuring a much longer lifespan.
• Reaction to fire
Materials with a high fire rating should always be used on ventilated cladding. EQUITONE’s fibre cement facades are A2-s1,d0 rated meaning they have negligible contribution to fire.
• Sustainable
EQUITONE is the only fibre cement rainscreen panel manufacturer to have achieved Bronze Level Cradle to Cradle certification which is a high measure of sustainability.
• Aesthetics
EQUITONE offers a wide choice of colours, textures and finishes and can even mimic natural materials, enabling architects to create a visually striking contemporary aesthetic.
At EQUITONE, we are happy to help evaluate your project’s needs and to demonstrate how our rainscreen products will make your design beautiful. Click here to contact us.