Like many other countries, the presence of wasteful activities is very common in Kazakhstan’s construction industry. This severely affects the productivity of construction processes. Lean methodology maximizes the value of a process by minimizing wasteful or non-value adding (NVA) activities. This study aims to explore and quantify the impact NVA items on construction productivity. Several observations were made for construction processes in Astana, Kazakhstan to investigate and quantify various types of wasteful activities. Moreover, a survey was conducted to examine the general understanding of wasteful activities and Lean methods within the construction industry in Kazakhstan. In terms of wasteful activities, a similarity was found between the observed construction processes and survey results. Furthermore, apart from the commonly found seven types of wasteful activities, some other sources of waste, such as “preparation” and “break”, were found from the observations. Finally, wasteful activities were mapped with commonly used Lean tools, as found in the literature, so that productivity can be improved by minimizing NVA activities. From the mapping and the survey results, value stream mapping (VSM) was found to be the most effective Lean tool, since it facilitates increased visualization.