Zircon Industry Association, 24 Old Bond Street, Mayfair, London W1S 4AP, UK
A recent study showed that zircon-containing ceramic roof tiles increase solar reflectance, potentially reducing the urban heat island effect and lowering demand for the internal cooling of buildings. The study clearly demonstrates that zircon can help architects and specifiers to lower the environmental footprint of buildings they design and build, enabling compliance with green building standards and supporting bids to achieve LEED (Leadership in Energy and Environmental Design) ratings for their buildings.
A paper summarising the findings of the recent study, presented at the ECerS conference in Turin in 2019, reported how building envelopes using zircon-containing ceramic tiles improve the thermal comfort within the building by reducing energy requirements. When compared to other existing solutions including paints and cool paints, it also reduced maintenance costs due to the high resistance of ceramic tiles to wear, dirt and stains. It is clear that by actively choosing zircon-containing tiles for the building envelope, architects and their clients can significantly reduce the overall environmental impact of the building, while lessening the roof maintenance required over time.
This recent study, coupled with the recent Life Cycle Assessment (LCA) of zircon sand, demonstrates the value and benefit of zircon as a material in today’s modern world where there is an increasing pressure to minimise our environmental impact.
The ZIA and Centro Ceramico (Bologna) commissioned study evaluated the effect of adding zircon to ceramic glazes of various colours. Carried out both on a laboratory-scale and by field trials, zircon was added to 36 tile samples both as an opacifier directly into the glaze formulation (up to 10wt%), and as frit component (up to 6.6 wt%). The solar reflective index (SRI) was calculated on all samples.
Results of tests carried out on the samples of glazed ceramic tiles show that, in general, the addition of zircon increases the solar reflectance index (SRI) of the glazes, the effect being more pronounced when zircon is added as an opacifier. Monitoring of the surface temperatures of the tile samples when exposed outdoors to solar radiation confirms that the higher values of brightness and solar reflectance parameters of the glaze are associated entirely to the addition of zircon.