Brian Newell of Shackerley explains how ceramic granite can transform buildings thanks to a mixture of durability and design versatility .
Ventilated facade cladding is well proven and widely used as an aesthetically versatile approach to completing the building envelope, also offering benefits in terms of building lifecycle, thermal performance and maintenance. Specified for new developments and existing properties, this method of construction is seen across all sectors.
Not all ventilated cladding systems are the same, however. Architects working on conservation schemes which require natural or sympathetic materials are benefitting from the specification of a ceramic granite ventilated facade. This type of cladding was introduced to the UK in the early 2000s and continued innovation has led to the availability of increasingly large ceramic granite panels, up to 3200 mm x 1600 mm (11 mm to 20 mm deep) along with an ever increasing choice of colour palette, styling options and textures.
Ceramic granite is a versatile and technically-advanced material, is produced from natural elements to provide a finish that combines practicality and quality with the beauty of natural quarried stone.
Clays, feldspars, minerals and metal oxides are amalgamated and subjected to intense hydraulic pressure to create large format slabs fired at 12,600°C until fully vitrified. This fuses all the material’s constituent parts, so no bonding agents are required. The finished product can be specified with a natural, honed, or highly polished finish and can be produced in a remarkable range of contemporary styles and patterns in addition to traditional stone-like options.
Ceramic granite panels are engineered to be impermeable and exceptionally strong; panels of just 11 mm thickness can be relied upon to provide outstanding building protection. They are lighter and easier to handle and install compared to their quarried stone counterparts, and the loads on the building and the sub-structure are much lower.
For contemporary buildings, ceramic granite can offer a modern finish, for example with highly polished black, white and coloured panels providing striking contrast with curtain walling and glazing. Body veining and graining, highly polished, honed, satin lustre or natural finishes can be further enhanced by mixing panel sizes and orientation.
Advanced manufacturing technology has made it possible to produce ceramic granite panels that resemble other materials, including natural timbers. Ceramic granite can also be manufactured with a natural stone-like finish such as granite, marble or limestone.
As well as offering high aesthetic quality on completion, UV, weather and algae growth resistance will allow facades to retain their looks throughout the lifecycle.
Whereas most types of quarried stone are porous, ceramic granite is impermeable, which also contributes to the lifecycle performance of the building. Zero porosity ensures facades are resistant to all climatic conditions, and they comply with international standards for freeze-thaw resistance. The material is also impervious to airborne pollutants, most acids, alkalis and graffiti.
The longevity and performance of a ceramic granite facade will depend on the support system used to install it. The material can accept anchored undercut fixings which are invisible from the front of the facade. When used as part of the dedicated cladding support system with aluminium brackets, stress free anchorage results in a facade that is exceptionally resilient to structural movement, surpassing mandatory requirements for facades in earthquake zones.
Like all ventilated facade systems, ceramic granite facades allow a continuous flow of air in the cavity between the outer facade and the building exterior, creating a micro-ventilation effect that allows the building to ‘breathe’. This cavity allows for the installation of thermal and acoustic insulation to boost the building’s energy performance and interior comfort levels. Enhancing a building’s sustainability credentials in this way, as well as its service life expectancy and low maintenance durability has contributed to many project’s BREEAM ratings.
As architects come under increasing pressure to consider specification on a whole life costs basis and select products that will minimise maintenance and optimise aesthetics across the building’s lifecycle, ceramic granite ventilated cladding is becoming a popular choice.
Brian Newell is founder and chairman of Shackerley (Holdings) Group.