It is commonly accepted that façades require profound maintenance and/or partial renovation/replacement after 20 to 30 years following the construction (Martinez et al. Recent improvements in quality of biomaterials enable contractors to guarantee longer periods without maintenance, as well as to schedule the maintenance in advance. Fortunately, biomaterials are continuously improving and becoming more resistant to deterioration. At the same time, regular maintenance of façades is undesired among building owners. Designers are often not willing to implement novel solutions with improved durability and low maintenance requirements, because they are not confident in their performance. However, the choice of proper materials is still challenging. To minimize mistakes in façade construction, modern design standards follow current building codes and specifications. Those drawbacks are mainly related to poor design of construction details, improper choice or/and application of materials, and inadequate maintenance.

Flores-Colen and de Brito ( 2010) listed several difficulties related to the performance of building façades. Consequently, proper façade design has become a challenging and demanding task. Over time, façade complexity evolved to accommodate a wide range of functionalities. ( 2015), façades have a role in security, thermal and acoustical insulation, air and water infiltration/mitigation, solar, daylight and glare control as well as in aesthetics. Façades directly influence building safety, comfort, and aesthetics.

Deteriorating secondary deflector