The window is one of the most important aspects of a building. It aims to obtain good lighting and meet the requirements for Indoor Air Quality. A restroom is a place where most surfaces are wet, and it causes the relative humidity to become high. As a result, lighting must be considered in this space. The men’s toilet on the second floor of the Bina Nusantara University campus in Malang is the subject of this research. Interviews with building operators, cleaners and firsthand surveys of the location were also undertaken. The author used the results of interviews to help specify the ventilation system. The author utilizes a lux meter to measure the lighting layout. According to the findings, this toilet uses mechanical ventilation in the form of an exhaust fan. On the other hand, this area employs downlights that meet lighting standards in terms of brightness and color temperature selection in the artificial lighting system. In the current situation, there is a shortage of energy efficiency. As a result, this study offers a method for preserving electrical energy. This study uses an Arduino Mega and several sensors to help automate the operation of these electrical devices.