Photocatalytic self-cleaning coatings for building façade maintenance. Performance analysis through a case-study application.


  • Annalisa Andaloro Politecnico di Milano, Architecture Built Environment and Construction Engineering
  • Enrico Sergio Mazzucchelli Politecnico di Milano, Architecture Built Environment and Construction Engineering
  • Angelo Lucchini Politecnico di Milano, Architecture Built Environment and Construction Engineering




Façade maintenance, Cladding, Photocatalysis, Self-cleaning coating, Retrofit


Façade maintenance has become a key aspect in building management, due the specific actions involved and operation related costs. In this frame, the application of titanium dioxide photocatalytic sol-gel products on façade elements offers a wide range of opportunities to ensure proper functionalities maintenance overtime. This paper illustrates the self-cleaning performance of titanium dioxide and silicon dioxide based coatings applied to different kind of cladding materials. All tested samples were opaque. Preliminary laboratory tests were performed to verify hydrophobic and hydrophilic behaviour, prior to outdoor application, through water contact angle measurements. Afterwards, outdoor tests were performed to monitor color variation during 36 months to verify product effectiveness and its durability. Results proved that the application of functionalized nanotechnological coating to façade can significantly ease cleaning operations and reduce their necessary frequency over time. In addition, output provide some preliminary information about exposure condition influence on self-cleaning performance, which could be further investigated in the future. 

How to Cite

Andaloro, A., Mazzucchelli, E. S., & Lucchini, A. (2016). Photocatalytic self-cleaning coatings for building façade maintenance. Performance analysis through a case-study application. Journal of Facade Design and Engineering, 4(3-4), 115–129.




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