This research aims to explore the use of vegetation and nets to collect water from fog on facades to meet the needs of buildings’ functional requirements, particularly outdoor thermal comfort, water demands, and encouraging sustainability by suggesting a new architectural green–blue wall system. The system is posited to be applicable within an urban context, given its minimal spatial requirements and adaptability to existing structures. However, similar challenges to those encountered by green walls are anticipated, wherein the provision of sustainable benefits is offset by the demands of maintenance and associated additional costs. For this reason, this paper is mainly divided into two parts: in the first part, green facades are explained, referring to their effect on urban environment, including thermal comfort, pollution absorption, noise pollution, and well-being, as well as types of plants to apply on green walls; the second part focuses on the fog collector as an irrigation system for green walls, analyzing its components, structure, and fabric, to identify its development margins in the construction industry. Fog harvesting initiatives predominantly focus on rural regions to cater to agricultural demands; however, limiting fog harvesting to agricultural settings is considered insufficient, as it represents a crucial solution for addressing water challenges in specific urban environments. Nevertheless, it is worth investigating the fog collector’s potential for integrating water supply in urban environments as well. The study focuses on exploring the environmental benefits of fog harvesting and green walls, particularly through their combined implementation. The proposed review is significant for guiding the integration of a device into green facades, ensuring water self-sufficiency while concurrently addressing air purification, noise reduction, and thermal comfort for pedestrians and urban inhabitants. Nevertheless, it is worth investigating the fog collector’s potential for integrating water supply in urban environments as well. The proposed review is, therefore, useful for integrating a device represented by the fog harvesting system, also identified in the text as the blue system, into the design of green facades, identified in the text as the green system, integrating the blue element in the design of the green wall to make them water self-sufficient and at the same time purifying the air, reducing noise pollution, or giving thermal comfort to pedestrians and inhabitants of the urban context.

Fog harvesting is a technique used to collect water from the fog. This technique became widely used around the world due to the lack of fresh water, as fog harvesting is considered to represent an economical and a reliable source of water. On that sense, fog collecting methods are mostly implemented in areas that lack access to fresh water and is mostly used for agricultural purposes and, in some cases, also for providing clean drinking water. The basic idea of harvesting the fog was first developed by farmers when some types of adjoining cavities and containers were put around plants to collect water from humid air, after that those techniques were turned into fog harvesting structures. The introduction of fog harvesting techniques was accompanied with the introduction of new materials and different structures, providing a range of options in regards to the meshes and to the harvesting methods. In this paper, a practical and theoretical assessment of existing fog harvesting meshes is performed in order to characterize their economic and physical characteristics. The final objective is to provide information about their ability to perform in different conditions which is to be added to an environmental conditioning structure for exterior spaces.