Last Planner System is the lean tool for better scheduling, control and coordination of craftsman activities during the construction phase.
LPS offers the solution to the known problem. The schedules have often proved unreliable, and many construction projects have been handed over too late or cause coercive and/or daily fines. That the fear of delays causes some projects to be planned too long is also a waste. The theory behind LPS is that due to the unpredictable nature of construction projects, it is not possible to plan a construction project from the beginning on a retail basis. Therefore, it will be more efficient to plan the design in a more general framework and to wait with the planning of the individual activities until they are about to be implemented – hence the name Last Planner System.
Another important factor is that the detailed planning should not be carried out by the site management but by those who actually have to carry out the activities, ie. the craftsmen themselves. In this way the practical experience of craftsmen, for example the knowledge of the duration of the activities and the connections to the activities of other departments, are included. It has been shown that the cooperation specified at the planning meetings usually only really takes place when the craftsmen were able to coordinate themselves more strongly. Last but not least, the craftsmen focus more on the timetable they have created themselves than on the one specified by the construction management.
LPS is based on Lean principles, including the fact that higher productivity in a production chain can not be achieved by looking at the individual activities, but through the whole process, ie. including preparation and availability. At the activity level, the theory is that seven conditions must be met before an activity can be executed and called intact – “flow”. The 7 main activities are:
Previous work must be completed
There must be space
Drawings and other information must be available
Qualified personnel must be present to carry out the work
The resources/materials must be in place and have the right quality
The equipment/equipment must be in place and in order
Weather, permits, etc. – The external conditions must be in order
Weekly meetings and the work schedule
If only one condition is not met, the work can not be performed. For example, if there is an uncertainty of 5% in each of the 7 conditions, it means that the likelihood that the activity is ready to execute is only about 70%. So you do not have to be very flawed before delays occur. Systematic follow-up of the 7 conditions ensures that the activities can be carried out as planned.
The LPS method will be implemented in a series of meetings. It starts with a planning workshop, in which the process plan for the current production area is determined between the building management and the units that will carry out the work. The result of the planning meeting is a detailed work schedule for the design. Following the planning workshop, weekly meetings will be held to follow the work plan and work of the coming week. The meeting selects a portion of the schedule, such as 5 weeks, and tracks the 7 main flows. Potential obstacles are listed on an obstacle list of people in charge and deadlines to ensure that they are overcome. Intact activities come on the weekly schedule, according to which the craftsmen work.
LPS combined with location-based scheduling
When the LPS method was introduced in Denmark, the use of digital time-planning tools in the industry was limited to, for example, MS Project and Plancon, i.e. bar charts. Since then, location-based planning based on data from 3D models has become an option that offers new opportunities, as well as challenges to adding value to the LPS method. For more information about location-based planning, see here.
Egil Rasmussen, Fredericia
“From now on, we will introduce the method (site-based planning) for all our construction projects. In my view, location-based scheduling in combination with the quantity planner is the optimal way to execute a schedule.”