Ingenieur Vol.82 April-June2020 | Page 16

INGENIEUR for more than 100% of their capacity to meet targets due to inconsistency in the pace of work (Kanban Zone, 2019). Hence, Muri can result from Mura and then lead to Muda. Muri can be avoided through standardised work sequences by defining a standard condition (Hubbard, 2010). Types of Waste Lean management aims to remove wastes from work processes. A major focus of Lean Construction and Lean Planning is to reduce waste in every aspect of a construction project and thus reduce or minimise the cost of any process that the client or the owner of the construction project does not wish to pay for. There are eight types of waste that need to be considered as discussed below. The Eight types of waste Seven types of waste were first identified in the Toyota Production System and an eighth – non-utilised talent – was added when the lean methodology was adopted in the Western world. This is directly related to management’s ability to utilise personnel (Gay, 2016). Figure 2 explains the eight types of waste that need to be assessed in the construction process. Factors Affecting Wastes in Construction There are several factors that influence waste generation in a construction project as shown in Figure 3. Best Productivity Practices for Good Construction Waste Management Achieving the main goals of productive construction does not just involve one party starting and implementing action. Collaborative support and action through multi-sectoral partnerships will result in good construction waste management. Despite there being many issues that can cause construction waste, there are several productivity initiatives that would solve many construction waste activities and result in 1 2 3 4 5 6 Frequent Changes in Design Usually occurs as the client provides several last-minute changes during the life time of the project. This is mainly caused by the lack of communication between different project parties and the lack of understanding of the client’s requirements. Any changes in design will lead to rebuilding and changed designs and specifications. This costs time and money. Mistakes from Workers Improper training, poor working skills, bad work attitudes, work overload, poor management by senior engineers or supervisors etc. can cause mistakes that will eventually generate waste. Mistakes caused by workers can also affect the quality of the work produced by them. Weather Conditions Variations in weather conditions is one of the major external factors that can generate waste in construction projects. Weather conditions can force rescheduling of project plans which lead to delays and extra costs over the estimated budget. Improper Storing of Materials Materials should be handled and stored properly to protect them from any adverse weather conditions. Improper storing can lead to cracks and defects which will need replacement of materials. Error in Purchasing Ordering or purchasing over or under the required limit can generate extra costs or generate delays. Sometimes an error in purchasing can result in poor quality materials i.e. the wrong type or materials that do not fit the required dimensions. Poor Planning Planning and management can severely influence the amount of waste. Poor planning can be a major cause of waste generation as it can lead to multiple types and amounts of waste. (Source: Mydin et al., 2014) Figure 3. Factors affecting waste in construction 14 VOL 82 APRIL-JUNE 2020