Fire emergencies pose significant risks, with conventional alarms often lacking rapid response mechanisms. Delays in manual intervention can lead to severe consequences in residential and industrial settings. This study presents the Domestic Emergency System (DES), an IoT-integrated, multi-layered fire detection and emergency response framework. DES utilizes flame and smoke sensors, GSM-based emergency dialing, and RF communication modules to enable real-time hazard detection, structured evacuation, and automated alerts. An adaptive thresholding algorithm minimizes false alarms while ensuring precise fire identification. Experimental validation demonstrated fire detection within 0.8 s, RF signal propagation up to 25 m, and emergency call execution within 5 s, improving response time by 70% compared to traditional alarms. The multi-tier alert mechanism and mobile notifications enhances situational awareness and security coordination. The DES framework outperforms conventional fire alarm systems by integrating automated emergency calling, RF-enabled intra-building communication, and a resilient multi-modal alert system. Its scalability and adaptability to smart city infrastructure make it a transformative solution for modern safety applications.