The increasing demand for energy-efficient, secure, and remotely accessible home automation systems has led to the advancement of IoT-based smart home solutions. This study presents a comprehensive IoT-based home automation system integrating multiple sensor nodes and a central control unit to enhance safety, energy efficiency, and user convenience. The system comprises five nodes: a Combustion Accident Warning Node (CAWN), a Weather Sensing & Regulation Node (WSRN), a Remote Domestic Appliances Operate Node (RDAON), an Automate Light Control Node (ALCN), and a Home Defense Node (HDN). The ESP32 microcontroller serves as the control hub, communicating with all nodes through Wi-Fi and Bluetooth for real-time monitoring and control. The proposed system utilizes infrared flame sensors, gas sensors, temperature and humidity sensors, LDRs, and relays to automate household appliances and security mechanisms. Experimental results indicate that the system reduces energy consumption by 33.7% compared to manual control and 22.2% compared to traditional timer-based automation, leading to significant cost savings. The Home Defense Node demonstrates over 90% intrusion detection accuracy with a response time of 100–300 ms, ensuring robust security. Additionally, real-time cloud integration via the Blynk IoT platform enables seamless remote operation. The findings suggest that the proposed smart home system offers a reliable, and scalable solution for modern home automation.