Construction industry is highly characterized by its low productivity due to the presence of wasteful activities in many forms. The key idea of lean principles is to maximize process value while minimizing waste. This study aims to explore and quantify the impact on construction productivity by non-value adding items. Several observations were made for construction operations in Astana, Kazakhstan to quantify various types of wasteful activities. It was observed that 26% activities were pure waste. Nevertheless, the literature study provided the percentage of non-value adding activities to be between 3665%. Moreover, other sources of waste such as “Preparation” and “Break” were found from the observations which do not fall under any of the existing 7 waste categories. A questionnaire survey was also conducted to examine the general understanding of non-value adding activities in construction. Most of the survey participants also indicated the presence of wasteful activities in the construction processes to be between 10-30%. Finally, to improve the construction productivity by properly quantifying the non-value adding activities, Value Stream Mapping (VSM) tool which is also evidenced by the survey result, was found to be most effective lean tool since it facilitates increased visualization.