An Experimental Study of Indoor Air Quality Enhancement Using Breathing Walls
Dalia Elgheznawy, Osama Abou El Enein, Ghada Shalaby, Amany Seif
Abstract
Recently, many studies have focused on studying indoor air quality, especially with the outbreak of COVID-19, which is one of the reasons for the increased need to improve indoor air quality. Many ideas and applications are available to incorporate nature into buildings to improve indoor air quality (IAQ) and thus secure a higher percentage of natural ventilation and pollution reduction. One of these ideas is to use "breathing walls" (BWs), which are envelope components based on porous materials. They decrease energy consumed for heating, ventilation, and air-conditioning of buildings. The study discusses the effect of using the BW approach on thermal comfort in buildings. Moreover, the improvement in the IAQ when using two models - one using BWs (applying natural and industrial materials together on the BWs, which are composed of wooden concrete hollow bricks (WCHBs)), and the other model built with solid traditional bricks (STB) - was studied through an experiment to compare air temperature, carbon dioxide (CO<sub>2</sub>) concentration, indoor relative humidity and thermal behavior. The experiments were conducted on the two models for five months in the summer of 2019, and the results of both models were compared. From the results, it may be concluded that the model with BWs exhibits improved thermal behavior than the model with traditional bricks by recording on average three to five degrees lower than the outside temperature. Moreover, the relative humidity is lower in the WCHB model than in the STB model by ~41.66% in the same conditions; however, the CO<sub>2</sub> concentration (ppm) in the WCHB model was lower than that in the STB model by ~28.5% in the same conditions.