Building lighting systems represent a significant economic and environmental burden due to their high energy consumption and operational costs. Additionally, the growing availability of data from multiple smart devices provides opportunities to optimize energy consumption in building lighting. Internet of Things (IoT) technologies offer an effective solution for managing energy use in building lighting systems by enabling real-time data gathering, transmission, and analysis. While initial studies have focused on communication technologies, limited attention has been given to the system’s hardware and software design. This study presents a design for an IoT-based smart wireless sensor node system aimed at optimizing energy consumption in building lighting, reducing operational costs while maintaining lighting quality. The design follows a 3-tier architecture comprising perception, communication, and application layers. Each smart node includes sensors and actuators for real-time monitoring and control, with communication supported through LoRa and mobile network technologies to enhance system performance.