Adam Sumner, specification manager at Pura Facades, thinks it’s time to re-evaluate the use of natural clay facades in building design.
Meaning “baked earth” in Italian, terracotta has a rich history as a building material dating back thousands of years. First used for practical items like storage jars, it was the Romans who particularly excelled in its architectural application in reliefs and building decoration. Terracotta experienced a revival in the 19th century, especially during the Victorian era, and continues to be a popular choice today.
However, in the rush to explore the latest innovations in cladding design – including glass reinforced concrete, solid aluminium, brick slips and fibre cement – it’s easy to overlook one of the oldest and most sustainable building materials known to man – terracotta clay.
While this historic building material has a reputation as a premium product, many architects and contractors mistakenly think it comes with a price tag to match and can only be used for landmark projects. In practice, this misunderstanding needs to be addressed – given the fact that in our experience terracotta is a relatively low-carbon, lightweight, attractive and keenly priced alternative to many other façade materials. It’s also much more flexible than many might think when it comes to aesthetic finishes, providing a huge array of attractive colours that also pass the ‘touch test’ demanded by fans of ‘biophilia’, the trend for materials to reflect nature.
More than just clay
Mention the word terracotta and most people think of earthy brown hues. And while this colour is timeless, many architects are now exploring the creative possibilities afforded by the addition of high gloss colours during the firing process.
A superb example of this approach in practice can be seen at the Maggie’s Centre in Nottingham. Designed by Piers Gough, this building uses striking green colours to clad a unique elliptical design, that sits within a wooded glade.
Another residential project, Sanctuary at Wentworth Point, Australia demonstrates the bold use of anthracite grey and bright red, both from Tonality’s Nature range of coloured tiles. Using Japanese design principles, this eye-catching development sits within a nature reserve, really showing off the creative possibilities realised by terracotta.
The perfect pair – terracotta and timber?
As the sole UK distributor of Tonality, the Austrian terracotta brand that uses exclusively high-grade Westerwald clay, we are seeing a rise in the use of this material especially in conjunction with timber. Thanks to the single-shell production method — which makes the ceramics significantly lighter compared to conventional solutions — the required substructure can be substantially reduced. The rear-ventilated ceramic facade from Tonality, which incorporates internal insulation, also minimizes the construction depth of the facade — eliminating the need for complex substructures.
Timber buildings using terracotta facades thus benefit from both significant weight and cost reductions in facade planning, as well as from excellent fire protection properties and a wide variety of design options.
Reasons for this trend, most notably in Europe but also the UK, include the adoption of prefabrication and resource-efficient building methods. In this context, we have seen a growing interest from architects in ceramic facades for timber buildings. The Pertinsel children’s nursery in Fussach, Austria is a good example of terracotta façade being used alongside natural wood to create a warm, natural look.
Single-shell benefits
The single-shell ceramic facade panels we supply have a low surface weight of only around 40 kilograms per square metre. In comparison, double-shell ceramics weigh around 60 kilograms per square metre or more — often making them practically unsuitable for use in timber construction.
Despite their single-shell design, Tonality ceramics offer full flexibility in profiling: with tile depths of up to 29mm being easily achievable. A recent EPD (Environmental Product Declaration) confirms that these materials and production processes meet the highest sustainability standards. Phases A1 to A3 (raw materials, transport to factory, manufacturing) generate just 18.5 kilograms of CO₂ equivalents per square metre. Including phases A1 to A5 (raw materials, transport to factory, manufacturing, transport, installation), the figure is 20.95 kilograms of CO₂ equivalents per square metre.
A question of cost
Contractors and architects alike often write off terracotta as an expensive façade material, given the fact that it is a high quality, natural product in our case manufactured in Europe. However, in our experience, as long as careful design planning is employed to retain simplicity, terracotta can often be more cost effective than other façade options, offering improved longevity and aesthetics.
Take for example the recently completed project at St George’s Island Manchester, which involved the cladding of five blocks of apartments in Castlefield, a highly desirable canal-side area of the city.
Using a set of standard sizes and grid heights, we were able to achieve a high quality, terracotta finish on this development at a cost of approximately £65 per m2. That’s a very competitive price, which brought genuine quality, safety and value to the building, costing less than a lot of competitive cladding alternatives such as glass reinforced concrete or solid, coated aluminium.
The lesson here? It’s important to consider all options and not be swayed by untested, preconceived assumptions about a specific façade option. It’s all about the specific project and the particular cladding solution you are assessing for use.
Fire Protection as a Deciding Factor
The ceramic elements of terracotta are classified as building material class A1, meaning they are non-combustible and contain no flammable components. More planners are favouring ceramic facades for fire protection reasons. Moreover, for certain building categories, expensive sprinkler systems are often required for timber facades. In some cases, the use of a ceramic facade can eliminate this requirement — depending on regional or project-specific fire safety regulations.
Maximising the footprint
Rear-ventilated ceramic facade tiles also ensure a particularly slim wall build-up on projects. Because the required insulation is placed internally and the single-shell ceramic is approximately 30mm thinner than a double-shell ceramic panel, it does not add extra thickness to the facade — and in fact can even reduce the overall depth. This results in more rentable interior space — a major advantage especially in boundary developments where every centimetre matters.
For developers, approximately 20 to 24cm of saved insulation thickness can be credited to the usable interior space. The product also offers high flexibility regarding tolerances: adjustments between 20mm and 60mm can easily be accommodated. Another advantage of ceramic facades is their ability to be fully recycled, remaining within the circular construction economy.
Off-site fabrication
In this context, Vivalda is also working with suppliers such as Tonality to increase the level of prefabrication of ceramic facades for projects. For example, it is conceivable that the substructure could be preassembled at the factory and delivered to the construction site as a finished module. There, the ceramic façade would simply need to be hung in place — developments aimed at promoting modular construction, relieving skilled labourers, and accelerating building progress.
As a building material dating back thousands of years, terracotta is yet again proving its worth as a safe, flexible, attractive and cost-effective façade choice.