Urban Facades

Abstract

Air pollution is a worldwide prevailing issue affecting the health of human beings in urban areas requiring urgent measures to adopted. This graduation project targets on adoption of passive air remediation techniques that can be widely applied into urban areas. Within the passive technical measures available, integrating greeneries on the infrastructure and photocatalytic materials prove promising to be incorporated in a broader perspective. Photocatalytic materials one-time installation, easy to maintain and self-cleaning properties has led to the selection of this material to quantify its air purifying capability.
TiO2 coating has been used in building materials for its self-cleaning property. However, its capability to break down NOx compounds has broadened its scope for pollution abatement. Though it can be applied as a coating, the performance of the photocatalyst in urban scenarios is affected by contact wind speeds and incident UV irradiation. Also, increased surface area provides more area of photo catalytically active sites. These factors are governed by the geometrical form of the panel. Hence, the main objective of this research is to design a façade panel with enlarged surface area and surface roughness to manipulate the environmental factors to favor photocatalysis. Also, its air purification effect is quantified to understand the effectiveness of this passive strategy and the design.
The façade concept has been designed following a series of strategies to respond to wind and irradiation. The concept with optimum surface enlargement and irradiation is developed into modular panels which are materialized by choosing the material with least environmental impact. The final part of this graduation project is about applying these panels in the street canyons, a controlled urban environment and evaluating the pollution abatement. The results indicate a pollution abatement of 3.5% - 8.9% in winter and 18% - 37.5% in percentage in summer for London.