The growing considerations of people, profit and planet have emphasized the integration of sustainable concepts in the construction processes. The previous research in sustainable construction has underlined the issues pertaining to raw material and its manufacturing; design aspects along with the occupancy phase of a building life cycle. However, concerned over GHG emissions from the operation of non-road diesel equipment are still being ignored in the established literature. These non-road construction equipment consume fossil fuel and a serious threat for green environment. In addition to this, health and safety issues are also important concerns for the human well-being. Thus, mitigating these impacts are the important aspects of sustainable planning for onsite construction activities. A questionnaire survey was carried out to explore the contractors views towards potential challenges that are relevant with the growing attention of sustainability in construction sector. A group of large civil contractors of Malaysian construction industry were solicited through online survey to prioritize the potential barriers. The research findings presents a broader view and a number of challenges that inhibits the contractors for acquiring, adopting and implementing sustainable practices for onsite mechanized construction activities. © (2014) Trans Tech Publications, Switzerland.