Rainscreen cladding is an effective, reliable construction method applied to protect buildings from the elements. QI Building Solutions were one of the first to introduce this method, which is one of the most popular choices for new construction and restoration projects across all sectors of the industry today.
Q: What are the benefits of rain screen cladding?
A: Rain screen cladding keeps your home warm, protects against wind strength, helps manage water infiltration, and generally provides a powerful barrier against the elements.
Raincladding systems in the UK
Common types of rain screen cladding and external wall cladding systems in the UK include vented drained cladding, enamel cladding, and pressure-equalised (or moderated) cladding. We work with Sto, Knauf, and Kingspan among other leading brands. Read on for more information about them.
The StoVentec R cladding system is fixed to an outer wall using an adjustable aluminum substructure, forming a cavity between the render carrier board and façade, which is partially filled with mineral fibre insulation. The system keeps the wall dry and allows it to breathe. The finish can be very light because the cavity is ventilated. The adjustable stainless steel substructure corrects uneven substrates, while the mineral fibre insulation board guarantees fire safety and high thermal performance.
This company’s K15 Rainscreen Board features fiber–free rigid thermoset phenolic insulation core, with bilateral, low-emission composite foil facing. It serves as excellent insulation for our rain screen cladding systems. The core of the board is made with a blowing agent with low Global Warming Potential (GWP) and no Ozone Depletion Potential (ODP) at all.
Knauf features a wide variety of proprietary rain screen cladding systems. Most of them entail installing the insulation on the outer side of a masonry wall to maintain stable internal temperatures by reducing heat in the summer and storing it in winter.
Among our other reputable partners are Alsecco, Dupont, Rockwool, Florim, CGL Facades and Valcan.
Cladding consists of vertical fixing rails, a rainscreen slab, a double plasterboard layer, rainscreen brackets, thermal break pads, a cement fibre board, and a vapour control layer. Below is an image of typical cladding:
Vented Drained Cladding
Vented drained cladding construction consists of a ventilation cavity, a weather-resistant outer layer, and an inner layer to create protection against moisture. It also keeps your property warm because it provides thermal insulation. Professionally installed rain screen cladding is designed to manage UV radiation, water infiltration, thermal transfer, and pressure from the wind. The outer layer is the main barrier against rain, wind, and other elements. It is usually made from robust, durable materials such as high-pressure laminate, aluminum, or polished stone cladding.
The inner skin of the rain screen system is the second barrier keeping moisture from penetrating the external cladding. The air ventilation dries any water that passes through and ventilates moisture in the air. The ingenious insulation and ventilation systems work in combination to increase airflow and keep the building warm by restricting the flow of energy in and out of it.
This type of rain screen cladding features robust architectural cladding panels with a highly durable finish. The enamel coating has very good impact and scratch resistance, making it the ideal choice in heavy traffic or high-wear areas. It is also highly resistant to acids. When compared to more conventional cladding types, it demonstrates superior colour consistency. The colour of enamel panels is affected by the elements to a lesser extent. In some cases, its original colour outlasts the life of a normal building.
Another benefit of enamel cladding is that it is non-combustible and low-maintenance. The surface is low-static and very smooth, preventing dust from sticking to the panels and requiring minimal cleaning.
Pressure-equalised rain screen cladding is where the ventilation openings are big enough for the air pressure to equalise on either side of the panels. This system is best for buildings with a height of over 12 meters. Pressure-equalised cladding systems are based on the principle of balancing flow of air and water through the building envelope. In essence, one works with the forces of nature rather than against them.
Benefits of rainscreen cladding
All types of rainscreen cladding systems share a number of benefits, the main ones being that they’re lightweight, easy to install, fixed with minimal waste, do away with the need for wet trades, and are durable and low-maintenance.
In addition, rain screen cladding is aesthetically pleasing without compromising on safety and structural performance. Various designs are possible, and there is great versatility when it comes to structural design framing and installation systems. The range of materials and finishes is extensive, and main structure contact points are thermally isolated.
How to fix rainscreen cladding
Most commonly, rain screen cladding is fixed using metal brackets, which are installed on each side of the vertical profile in alternate courses. You need to use both metal brackets with a sliding point and fixed point metal brackets to make profile expansion possible. Fixed point metal brackets are located on the upper end of each profile.
After choosing the most appropriate insulation material, the ‘L’ shaped vertical profiles are fixed to the metal brackets. Make room of a few centimeters for an air cavity. Before fitting the rest of the system components, you must make sure the vertical profiles are completely level.
Ventilated flashing is fixed at the first course of the cladding, and metal flashings are fixed at single points such as window frames and edges. Horizontal profiles are fixed with vertical profiles at each intersection. The end slate position depends on the horizontal profiles, so the latter must be perfectly level. To make it possible to fix the first course slate, one needs to fit an inverted 101 horizontal profile at the first rain screen cladding course as well.
The first course slate is cut to an approximate height of 8 cm and fixed inverted, matching the slate’s bottom edge. Each slate could be fitted with self-drilling stainless steel screws and must be aligned with the upper edge of the profile. Finally, the top flashing is fixed.
Rain Screencladding cost
Rainscreen cladding systems range from £50-80 per m2 (Alsecco) depending on the finish to 100-120 per m2 (Sto). The most important measurement is how many square metres of walling you plan on covering. That’s the main aspect to take into account when calculating your order. We recommend adding around 8% to this number to account for wastage and cutting. Please contact us for detailed quotes, including materials and installation.