Internet of Things (IoT) visualizes future, in which the objects of everyday life are equipped with sensor technology for digital communication. IoT supports the concept of smart city, which aims to provide different services for the administration of the city and for the citizens. The important application of IoT is Structural Strength Recognition (SSR). This approach is becoming popular to increase the safety of buildings and human life. Proper maintenance of historical buildings requires continuous monitoring and current conditions of it. Sensor nodes are used to collect data of these historical buildings or large structures. Structural strength recognition covers huge geographical area and it requires continuous monitoring of it. It involves more energy consumption during these activities. Hence, there is need for efficient energy management technique. Clustering is one of the important techniques for energy management in Wireless Sensor Networks (WSN). It helps in reducing the energy consumed in wireless data transmission. In this paper, SSR system is designed with efficient clustering algorithm for wide network and also finds out optimum number of clusters. © 2018, Springer Nature Singapore Pte Ltd.