Review on Energy and Fire Performance of Water Wall Systems as a Green Building Façade

Glass façades are widely utilized in green buildings. Ensuring fire safety while reducing the energy need without compromising occupants’ comfort is a challenge in the modern-day green buildings with glass façades. One way of achieving both aspects is to construct a water wall system as a building façade. A water wall system has a water layer between two glass panes and can be considered as a glass façade system. The focus of this review, which builds on the published studies, is how water wall systems can help ensure fire safety and reduce energy demand in green buildings. The water layer within two glass panes of the water wall system store the solar radiation heat throughout the daytime, reducing the amount of heat transferred through the building facade. The reduced heat transfer effects lessen the need for air conditioning to sustain the thermal comfort of the building occupants. The stored energy is released during the nighttime. The transparency of the water wall system also allows daylight to enter the building, thus reducing artificial lighting needs. Furthermore, the water layer acts as a fire safety mechanism in case of a fire. However, the water wall systems are not much utilized in the modern-day green buildings due to their unpopularity and the unavailability of design guidelines. On the basis of the findings of the literature review, stakeholders and the public are encouraged to adopt water wall systems in green building projects as an energy-efficient strategy and a fire safety mechanism.