Application of blockchain and smart contract for construction quality assurance in Hong Kong : potentials and limitations

Abstract

Construction quality, which has been under the spotlight in Hong Kong in recent years, does not only affect the functionality of the structure and the property value, but also possesses substantial implication on public safety. Hence, construction quality assurance (QA) plays an indispensable role in ensuring that the constructed infrastructure or building can live up to the statutory requirement, codes, and specifications in the contract. To promote the digitalization of the construction industry, and to facilitate QA process in a more transparent and collaborative environment, Digital Works Supervision System (DWSS) has been introduced by the Development Bureau of the HKSAR government for storage of information regarding the quality inspection forms and other workflows in the construction project, while other initiatives, such as blockchain solution, has also been explored to enhance construction QA process. Essentially, blockchain solution arises as trustworthiness is of utmost importance in QA. The emerging and revolutionary blockchain technology, alongside with its counterpart smart contract, facilitate the QA process in a more trustworthy, credible, transparent, and traceable way with a higher level of cybersecurity as blockchain technology guarantees the immutability of the record with timestamp and digital signature, encouraging personnel to conduct QA in a more prudent and meticulous approach, due to the establishment of accountability by the system. Meanwhile, smart contract further facilitates the automation of QA tasks with clear delineation of responsibility of each stakeholder in the project. Moreover, permissioned blockchain network shall be employed to ensure authorized access by stakeholders with different level of authorities to the blockchain network. More importantly, Internet of Things (IoT) could have tremendous synergistic effect with blockchain technology, especially for Modular Integrated Construction (MiC) project, such that true provenance of the quality information can be guaranteed, ensuring that the modules are delivered and installed intact at the right time, at the right place and with the right quality. Despite the competitive edges of leveraging blockchain technology and smart contract for QA over traditional information system, the solution is not without flaws and limitations in terms of technical aspect – latency and scalability problems are still prevalent in the blockchain network. Moreover, higher external cost and private cost may be incurred attributable to higher power consumption that leads to higher carbon emission and employment of the blockchain software and IoT sensors respectively. After all, whether application of blockchain and smart contract would be an optimal solution to construction QA depends on the project type and scale, the perceived value of blockchain technology by the stakeholders in the construction industry after weighing its cost and benefits, and most importantly, the evolution of technological advancement in the foreseeable future.