Lean Construction: Better Flow, Less Waste
Lean is not “work faster”. It is the systematic removal of waste: waiting, rework, excess movement, over-ordering, and poor information flow.
1. Constraint Management
Every week, identify constraints that will block upcoming work: drawings, approvals, materials, access, inspections. Then remove them before they become delays.
2. 5S on Site
Order and cleanliness reduce incidents and improve productivity. A tidy site is a faster site.
3. Last Planner Thinking
Commit to achievable weekly tasks with trade input. Measure plan reliability and learn from failures instead of blaming people.
4. Measure “Plan Reliability” (PPC)
A simple lean metric is Percent Plan Complete (PPC): the proportion of tasks promised last week that were actually completed. PPC turns planning into a learning system.
5. Examples of “Lean Wins” on Australian Sites
- Standardised bathrooms/kitchens: repeatable details reduce rework and speed finishing.
- Pre-cut and pre-assembled components: reduce site waste and improve quality (when the design is stable).
- Visual constraints board: makes approvals, missing info, and late deliveries visible to everyone.
6. Pull Planning (A Practical Starter)
Instead of pushing a programme onto trades, pull planning works backwards from a milestone (e.g., waterproofing sign-off, lock-up, PC). Trades identify prerequisites and realistic handovers. This often reveals hidden constraints early.
7. Takt Thinking (Without the Buzzwords)
On repetitive projects, aim for consistent “beat” per zone (floor, apartment stack, classroom block). Consistent flow reduces stacking, reduces defects, and makes forecasting easier.
8. Lean Anti-Patterns
- “Lean” as a slogan: posters without constraint removal is theatre.
- Over-planning: too much ceremony kills speed; keep it lightweight and consistent.
- Ignoring quality gates: flow without quality just creates faster rework.