Living walls in indoor environments

The warming climate, projected increase in frequency and severity of extreme heat events, and the long-established heat island phenomenon are all expected to exacerbate urban environmental thermal loading. Active means used for addressing such risks are likely to increase energy consumption and emission trends to create a positive feedback loop that could threaten the health and wellbeing of urban citizens. In response, passive approaches such as green infrastructure enhancements are widely advocated, and to meet the challenges of implementing enhancements in dense cities, attention has been directed toward encouraging surface greening. This paper recognises this trend and considers vertical greening as a developing interest with application opportunity in both exterior and interior urban environments. A review of available studies and interviews with experts found most observations available to be derived from exterior applications. Interior applications consequently have yet to be investigated to determine relative value to indoor environments where most of human habitation is typically concentrated. The integration of plant science studies in this regard is highlighted as essential to develop a balanced evidence base for the enthusiasm observed for promoting indoor living wall installations.