Creating flow
Go home Go to lean transformation
The great difference between a construction project and building a car is the flow, the movements of things. In the manufacturing industry, the product moves through different stations, but in the construction field the product is fixed in a place and needs to be transformed. With this approach, lean principles can also be applied in a construction project. In consequence, the flows to be analysed and optimised are:
· people
· materials
· information
· works units
The flow of information can be better managed using smartphones, tablets, project sites and 4G wifi to learn in real time what is happening. There are several software packages on the market to facilitate communication among all the participants in a project.
The next figure is the definition of activity according to Glenn Ballard:
If we consider the lean principle of pull, we´ll have in our projects inner customers, too. The team in charge of pouring concrete will be the inner customer of the subcontractor in charge of the steel in reinforced concrete.
Creating flow and going faster are the same. We create flow in our projects through offsite processes, quick ways of doing project activities, IT and standardized tasks. In consequence lead time will be reduced.
Value Stream Mapping is a very powerful lean tool visualizing the different processes and optimizing flow. In addition, you can work out the amount of value generated. A good book to read and learn is Learning to See by Mike Rother and John Shook. Doing the VSM is the second step of Lean Thinking and the third is creating flow.
In the manufacturing industry, it´s common to set inventory among tasks in the VSM. In the construction field, stocks or time can be showned among processes. You should graph (you need a paper and a pen to do a VSM) the current state, decide some improvements and do the future state. The next two figures are examples of a VSM in the construction of a hospital: (Glenn Ballard, 2008)
Flow-line or Line of Balance (LOB) is also useful to create flow. It´s used mainly in linear projects: skyscrapers, roads and tunnels.
Toyota uses a mechanism called “Andon” to help to create a stopping and solving habit. They even analyze the stops in production lines with Pareto Diagrams to determine the most common causes. It’s a good practice to discover the breaks of flow and to establish a learning culture. (Read Toyota Way by Liker for further information.)