# A Comprehensive Review of Sensor-Based Smart Building Monitoring and Data Gathering Techniques
###### Abstract  
In an era where buildings are increasingly becoming multifaceted entities, the paradigm of smart buildings has witnessed significant evolution. This advancement integrates sophisticated communication technologies, the Internet of Things (IoT), artificial intelligence (AI), and data analytics. Intending to design an effective smart building monitoring system, this research paper explores and compares various solutions for measuring building parameters by identifying a broad spectrum of review articles considering building occupant behavior, sensor deployment, and implementation complexity. The objective of our paper is to compile diverse information on various sensors used for monitoring building conditions and provide a comprehensive overview of data structuring and processing, all within a single article. Additionally, this paper addresses the challenges of combining data from decentralized systems and the need for managerial tools to optimize user experiences. The findings contribute to the advancement of smart building management, offering valuable insights for improving building performance and user experience as well as evaluating future research directions in this field. This review is designed to serve as an introduction for anyone venturing into the field of building monitoring. smart cities; smart buildings; Internet of Things; building monitoring; energy management; climate management; BACS; BMS; sensor data; data analysis +
Footnote †: journal: _Sciences_  
hardware, software, and communication resources to lower costs in a specific domain [6]. It ensures the transparency and visibility of complex systems as well as procures real-time monitoring [7; 8]. The architecture of the IoT is intentionally structured to equip all entities with identification, detection, networking, and processing capabilities, enabling them to exchange information seamlessly. Building equipment data collected from IoT sensors enable us to identify abnormal behavior in a monitored environment and predict and respond to anomalies [6]. Therefore, it is possible to make effective calculations based on the real-time environmental data produced by smart buildings and extend their features [8; 9]. Taking into account the above definitions, a smart building can be referred to as a building automation and control system (BACS). It is a modular, intelligent, automated system that unifies, integrates, and connects facility technologies through information flow to a central monitoring point. There are alternate terms for BACSs, such as building automation system (BAS) and building management system (BMS). Still, its core principle remains the same: facilitating information flow and automated decision making through connectivity [10]. The goal of BACSs is to control, monitor, and protect the building's operating environment by automating various systems, such as air conditioning, lighting, ventilation, and security systems. This enhances occupant comfort and reduces energy consumption, tailored to the building's specific purpose. The global BACS market is expected to experience a remarkable compound annual growth rate (CAGR) of 7.9% from 2023 to 2031 [11]. There are numerous strategies used to enhance the value of a building. However, when factoring in return on investment, cost efficiency, energy reduction potential, and tenant well-being, the most notable approaches are:  
* Indoor climate monitoring--helps to identify energy waste, allowing for corrective actions to prevent it, thereby reducing unnecessary energy costs and CO2 emissions. It also generates the data necessary for environmental, social, and governance (ESG) reporting as well as uncovers new energy efficiency insights. * Heating optimization--facilitates real-time temperature monitoring across various sections of a building, allowing for the regulation of district heating systems. This automated, real-time optimization process leads to substantial energy savings and enhances the comfort of tenants, facility managers, and other building occupants.