TEACHING LEAN CONSTRUCTION II: LAST PLANNER SYSTEM

3 August 2016

Glenn Ballard and Greg Howell developed the Last Planner System of Production Control throughout the 90s¹. At the same time, Lauri Koskela was working on developing a theory of production which provided the theoretical framework for the LPS². The LPS has been successfully implemented and is becoming an important part construction management³. However, the transition from theory to practice has not been easy. The LPS concepts can sometimes be too difficult to understand for those who lead the production process and have to implement it. The lack of practical tools to teach LPS encouraged us to develop this educational game.

THE GAME

The Pull Planning Lean Game© is an educational tool to teach Collaborative Planning and the Methodology of Last Planner® System. It was developed by the Think In Lean® Team and designed to teach the method under the specific approach of the AEC industry.

By playing this Lean game, attendees experience and practice for themselves the differences between a traditional planning and production control system and a Lean system. The game simulates the whole process of scheduling and building a house using PLAYMOBIL® pieces. The game consists of two rounds and can be played in a one-day session including:

Introduction to LPS / Examples.
Implementing / Simulating all elements of LPS:

Pull Planning Session.
6 Week Look Ahead Schedule Session.
Weekly Meeting.
Stand Up Meeting.
Implementation of Lean tools: Visual management, Poka-Yokes, Standardization and 5S.
Implementing a complete PDCA Deming Cycle

Ideally, this workshop should be delivered in a two-day session:

Day one: The Flow Building Lean Game© (See Teaching Lean Construction I)
Day two: The Pull Planning Lean Game©

Round 1

The main objective in Round 1 is to build a Playmobil® house by means of a traditional scheduling and production system. A secondary objective of this round is to get used to the roles, rules and the construction system, which could be related with the time we spend in a real project studying the real drawings and schedule. Time given to build the house in this round is 30 minutes and people normally build half the house or a bit more. By playing this round we realize the typical problems of a traditional project management system:

Identifying all Taiichi Ohno’s 7 wastes: overproduction (building before needed), no needed inventory, waiting (due to precedent task not ready), poor quality and re-work, over processing (assembling, disassembling and re-assembling parts; not needed processes), transport and motion. Gantt chart fails since the beginning.
Delivery delayed.
No time to react.
Problems explode on your face.
Lack of collaboration among owner, contractor, subcontractors and designers.
Lack of transparency.

Preparation for Round 2

Pull Planning Session
The Pull Planning is the core of this game. It lasts around one hour and attendees assume different roles as: contractor, sub-contractors, foreman, designer, and the client. Every sub-contractor is given a set of cards (a different colour for each sub-contractor) and the whole process of a Pull Session is simulated.

6 Week Look Ahead Plan Session
Once we finish the Pull Session, attendees perform the 6 Week Look Ahead Schedule. It lasts around half an hour, and discussion is encouraged in order to get the target of building the whole house in 20 minutes or less (five minutes per week, one per day).

Implementing Lean tools
During preparation time for round two, attendees are encouraged to implement other Lean Tools learned in the workshop as visual management, 5S, Standardization and Poka-Yokes.

Round 2

After implementing the LPS elements as well as some Lean tools, it’s time to play the second and definitive round. This time, attendees – performing the same roles as the ones in round 1 – must build the same house according to Lean Construction and Collaborative Planning principles and following the LPS methodology. Time is stopped every 5 minutes (representing a week), and a simulation of a weekly meeting is held.

During round 2 a PDCA (Plan-Do-Check-Act) Deming Cycle is performed at the end of every week, the Percent Plan Complete indicator (PPC) is calculated. Non-completion causes are discussed and Kaizen events are performed to achieve the target.

Conclusions

The Pull Planning Lean Game© has been a powerful educative tool to teach LPS and Collaborative Planning. The experience until now has demonstrated that the realistic simulation performed and the innovative educational methodology used allow attendees to understand the main concepts of LPS and start its implementation in a short period of time.