The primary aim of this research is to define smart construction objects (SCOs), the fundamental building blocks of future construction. SCOs are construction resources (e.g. machinery, device, and materials) that are made "smart" by augmenting them with technologies conferring autonomy, awareness, and the ability to interact with their vicinity. This "smartness" can enable better decision-making in construction. Understanding of SCOs, however, is still in its infancy. Informed by theories on ubiquitous computing and general smart objects, this paper firstly defines the core properties that differentiate SCOs from conventional construction objects. Secondly, representative scenarios of the use of SCOs are given to illustrate the new workflow with enhanced smartness in the future. Next, using prefabrication construction as an example, this paper further elaborates SCOs by using Industry Foundation Classes (IFC) Extensible Markup Language (XML) and exploring their software/hardware representations. This is the first-ever research to articulate canonical SCOs and their core properties, computing applications, and representations. More specific and applicable SCOs are compellingly desired as the future study. Properly linked to building information modeling (BIM) and Internet of Things (IoTs), SCOs can enable a safer, greener, more efficient, and more effective construction 2 system that has ever been seen.