Lean-ConstructionLPSLast-Planner-SystemPull-PlanningTakt-Time5SKanbanKaizenPDCAIPDBIMKPIsLean Construction Principles and Implementation FrameworkMay 22, 2024A comprehensive infographic detailing the core principles, tools, and methodologies of Lean Construction. Covers planning (LPS, Takt Time), workflow (VSM, JIT, 5S), problem-solving (Kaizen, PDCA), and collaborative delivery (IPD, BIM). 12. TECHNOLOGY INTEGRATION BIM USES 4D/5D, clash detection, quantities, layout • Clash tolerance: ≥ 25 mm hard clash detection • LOD: 300 design, 350 fabrication, 400 install • 4D takt simulation; zone sequence validation • 5D cost links; variance ≤ ±2% model vs. field • Model-based layout; GNSS/TS accuracy ±3 mm DIGITAL TOOLS Field apps, CDE, reality capture • CDE with version control; ISO 19650 metadata • Mobile ITPs; photo geotag + rev link • 360° capture weekly; deviation heatmaps • API sync to schedule/cost systems AUTOMATION & ROBOTICS Prefab, cobots, layout, QA automation • Prefab takt: module cycle 1–3 days • Robotic layout tolerance ±3 mm • Drones/LiDAR: scan-to-BIM weekly • Automated QA checklists; NFC sign-offs 11. PERFORMANCE METRICS KEY PERFORMANCE INDICATORS (KPIs) Flow, quality, safety, cost, delivery • PPC ≥ 85%, RFI cycle ≤ 48 h, NCRs < 0.5% • Schedule adherence ≥ 90% by phase • TRIR = 0; safety observations ≥ 2/worker/week • Cost: CPI ≥ 1.0, SPI ≥ 0.95 • Rework hours ≤ 2% of total MEASUREMENT & LEARNING SYSTEM Standard data capture and feedback loops • Daily logs: quantities, crew size, blockers • Digital forms; auto dashboards by zone/trade • Weekly retro using PPC variance categories • Action tracking closure ≤ 2 weeks VARIANCE ANALYSIS & ROOT CAUSE From symptom to cause with standard codes • 5 Whys; fishbone: method, machine, material, man • Reason codes: A design, B material, C labor, … • Corrective action with owner/date/evidence • Verify effectiveness in next PPC review 10. PROJECT DELIVERY INTEGRATED PROJECT DELIVERY (IPD) Aligned incentives, shared risk/reward • Multi-party contract (owner-designer-builder) • Target cost: validated estimate + risk reserve • Open-book cost, transparency dashboards • Big Room (OAC) cadence: weekly; RFI cycle ≤ 48 h • Pain/gain share tied to milestones COLLABORATIVE PLANNING Cross-trade huddles and constraint surfacing • Daily stand-up: 10 min; yesterday-today-roadblocks • Make-ready checklist per task • Visual backlog: WIP ≤ 2 per crew • Issue escalation path in 24/48 h TARGET VALUE DELIVERY (TVD) Design-to-budget with continuous cost feedback • Set target cost; track against allowance logs • Set-based design; options A/B/C within bounds • Cost model updates weekly; variance ≤ ±2% • Pull decisions to last responsible moment (LRD) 8. PROCESS OPTIMIZATION CONTINUOUS IMPROVEMENT (KAIZEN) Small, frequent changes owned by crews • Daily huddles: 10–15 min, PDCA cycle • Idea pipeline: ≥ 2 ideas/worker/month • Kaizen blitz: 1–3 days, target 20–50% waste cut • Visual A3s, owner + due date STANDARDIZATION & WORK INSTRUCTIONS Visual WIs with photos/steps Revision control and checks • WI format: steps, tools, spec, hazards, quality • Cycle time targets ±10%; CT measured weekly • Rev tagging: QR + rev/date/approver • Layered audits: foreman → PM monthly SMED & SETUP REDUCTION Convert internal → external; streamline changeovers • Map setup steps; separate while-running tasks • Target: setup ≤ 10 min per crew change • Quick-connects, pre-staged kits, color coding • Verify with before/after CT charts Value • Waste Elimination • Flow • Last Planner • Pull Planning • 5S • Kanban • Visual Management • IPD • BIM • KPIs • Continuous Improvement 1. CORE PRINCIPLES VALUE DEFINITION Translate customer needs to CTQs and tolerances • Voice of Customer → CTQ matrix (spec: ±2 mm finish, U-value ≤ 0.25 W/m²K) • Define value stream scope (design → handover) • Prioritize value: safety > quality > delivery > cost • Set takt targets (e.g., 1 unit/480 min/day) WASTE ELIMINATION (7+1) DOWNTIME + safety/info waste • Defects: rework < 1% by first-time quality checklists • Overproduction: limit batch size (≤ 1 day WIP) • Waiting: PPC > 85%, cycle time buffer ≤ 10% • Transport/Motion: point-of-use kits; 5S aisles 1.2 m • Extra Processing: standard details, BIM LOD 300+ FLOW OPTIMIZATION & TAKT Match capacity to demand rhythm across zones • Zone size = team capacity × takt (e.g., 50 m²/2 days) • Balanced crews: cycle time variance ≤ ±10% • FIFO handoffs; no leapfrogging between trades • Buffer strategy: 5% time + 2% material IMPLEMENTATION METHODOLOGIES LAST PLANNER SYSTEM (LPS) Commitment-based planning at the frontline • Milestone pull plans → phase plans (6–12 weeks) • Lookahead remove constraints (RFI, materials, access) • Weekly Work Plan: ready tasks only, trade commitments • PPC tracked weekly, target ≥ 85% • Variance reasons coded (A–H) for learning PULL PLANNING Downstream needs trigger upstream releases • Define done-criteria per handoff (spec, qty, time) • Limit WIP to 1–2 tasks/crew; kanban signals • Reverse-sequence phase mapping (sticky-note logic) • Buffer at phase boundaries: 1–2 takts LOOKAHEAD & CONSTRAINT REMOVAL Plan/Do/Check on a 6–8 week horizon • Constraint log: approvals, permits, designs, cranes • Ready-rules: design issued, shop-drawings approved • Material call-offs: JIT windows (±24 h) • Visual board: red tags cleared ≤ 5 days CULTURAL TRANSFORMATION LEAN LEADERSHIP Coach, remove roadblocks, model behaviors • Gemba walks: 1–2/week; observe, ask, support • Psychological safety; blameless retros • Enablement: tools, info, decisions at point-of-use • Standard leader work; cadence calendars TEAMWORK & COMMUNICATION Clear interfaces and information flow • RASCI per phase; handoff protocols • Standard meeting packs: 1-page status • Radio discipline; channel assignments • Visual kanban for RFIs/submittals TRAINING & INCENTIVES Skills, certifications, aligned rewards • TWI: Job Methods/Instruction/Relations • Certifications: LCI, BIM, safety (OSHA) • Incentives tied to PPC, safety, quality • Cross-training; multi-skilled crews 13. ORGANIZATIONAL ASPECTS Building Lean Culture Fostering a mindset of continuous improvement and respect. • Training programs reach 80% workforce, surveys score 4/5 engagement. • Promotes gemba walks, reducing silos 30%. • Long-term, yielding 15% productivity uplift. Leadership in Lean Champions driving lean initiatives from top-down. • Leaders model behaviors, allocating 10% time to lean coaching. • Sets vision, achieving 20% adoption rate in first year. • Example: Executive sponsorship for IPD contracts. Team Training Programs Workshops and education on lean tools and principles. • 2-3 day sessions, certifying 50+ employees/year. • Focus on tools like 5S, improving skills 25%. • ROI: 3:1 through reduced errors and waste. 2. TOOLS: PLANNING & SCHEDULING Last Planner System (LPS) Collaborative planning method that improves workflow reliability. • Weekly commitments from trade teams, targeting 70-85% PPC (Percent Plan Complete). • Reduces project delays by 25% via constraint removal and lookahead planning. • Applied in phases: master, phase, lookahead, and weekly planning. Pull Planning Scheduling by starting from the target completion date and working backward. • Identifies milestones and pulls tasks backward, ensuring just-in-time execution. • Improves on-time delivery by 30%, used in milestone planning sessions. • Involves sticky notes for tasks, durations typically 4-6 weeks lookahead. Takt Time Planning Balancing production pace with available resources and demand. • Calculates takt time as available time / units, e.g., 480 min / 10 units = 48 min/unit. • Reduces cycle time variance by 40%, applied in repetitive construction tasks. • Integrates with line balancing for even workflow distribution. Lookahead Planning Breaking the schedule into short-term, detailed plans. • 3-6 week horizon, identifying make-ready needs and constraints. • Enhances reliability, reducing rework by 15-20% in construction phases. • Uses screening, making ready, and pulling tasks for smooth execution. Visual mapping of processes to identify value-adding and non-value-adding steps. • Maps current and future states, highlighting wastes like waiting (up to 60% of time). • Reduces lead time by 35%, used in design and construction workflows. • Symbols: rectangles for processes, arrows for flow, kaizen bursts for improvements. Just-In-Time (JIT) Delivery Ensuring materials and equipment arrive exactly when needed. • Minimizes inventory costs by 20-30%, with delivery windows of 1-2 hours. • Integrated with pull systems, reducing site clutter and waste. • Example: Prefab components delivered daily based on takt time. Kanban System Visual task and inventory control system. • Uses cards/boards to signal needs, limiting WIP to 5-10 items per stage. • Improves flow, reducing cycle times by 25% in material handling. • Digital versions track real-time status in construction logistics. 5S System Sort, Set in order, Shine, Standardize, Sustain for workplace organization. • Reduces search time by 40%, audit scores target 80-100% compliance. • Applied to tools, sites; e.g., shadow boards for equipment. • Sustains through daily checklists and training. Value Stream Mapping (VSM) 3. TOOLS: WORKFLOW & WASTE REDUCTION 4. TOOLS: PROBLEM-SOLVING & CONTINUOUS IMPROVEMENT Kaizen Continuous improvement through small, incremental changes. • Events last 3-5 days, yielding 10-20% efficiency gains per process. • Engages frontline workers in suggestion systems, 50+ ideas/year/team. • Applied to reduce defects in concrete pouring, e.g. PDCA Cycle Plan, Do, Check, Act iterative improvement cycle. • Cycles repeat every 1-4 weeks, improving processes by 15% per iteration. • Used for testing changes, e.g., new safety protocols. • Metrics checked against baselines like time and cost. Plan Do Check Act Root Cause Analysis (RCA) Identifying underlying causes of issues. • 5 Whys technique drills down, e.g., to equipment failure roots. • Reduces recurrence by 50%, using fishbone diagrams for categories. • Applied post-incident, with timelines of 24-48 hours for initial review. A3 Problem-Solving Structured method for documenting and resolving problems. • A3 sheet format: background, current, goal, analysis, countermeasures. • Improves resolution time by 30%, used for delays in supply chain. • Involves team reviews, targeting 80% implementation rate. 6. TOOLS: COMMUNICATION & COLLABORATION Big Room / Obeya Co-locating project stakeholders for better collaboration. • Weekly meetings in shared space, reducing decision time by 50%. • Visual walls for plans, involving 10-20 stakeholders. • Enhances alignment in complex projects like hospitals. Daily Huddles / Stand-up Meetings Short, regular check-ins to keep teams aligned. • 10-15 min daily, covering tasks, issues, metrics. • Improves productivity 20%, with focus on impediments. • Used site-wide, tracking daily goals vs. actuals. Integrated Project Delivery (IPD) Collaborative contracting method aligning stakeholders’ goals. • Shared risk/reward, reducing claims by 40%. • Early involvement of all parties, cost savings 10-15%. • Contracts with KPIs for time, cost, quality. 5. TOOLS: QUALITY & SAFETY TOOLS Poka-Yoke Mistake-proofing design or process. • Devices prevent errors, e.g., color-coded wiring reducing mistakes by 90%. • Applied in assembly, with detection rates of 99% accuracy. • Types: prevention, detection; used in safety harness checks. Visual Management Using visual cues to make workflow, safety, and quality status obvious. • Boards show status, reducing miscommunication by 40%. • Safety signs and andons alert instantly, compliance 95%. • Example: Color zones for hazard areas on site. Standardized Work Documented best practices for tasks. • Charts detail steps, times (e.g., 5 min/task), reducing variation 25%. • Audits ensure adherence, used in installation processes. • Updates via kaizen, targeting zero defects. 7. TOOLS: PERFORMANCE EVALUATION Percent Plan Complete (PPC) Measures reliability of weekly work plans in LPS. • PPC = (completed tasks / planned) * 100, target 80%+. • Tracks weekly, improving from 50% to 85% over projects. • Correlates with 20% reduction in schedule variance. Task Variability Analysis Identifies and quantifies deviations in task durations. • Uses variance metrics, e.g., std dev of task times <10% target. • Reduces buffers by 15%, via histograms and root causes. • Applied to critical path activities in scheduling. Lean Metrics Dashboard Visual tool for tracking key lean performance indicators. • Monitors waste %, cycle time (e.g., <30 days), throughput. • Digital dashboards update real-time, improving decisions 25%. • Integrates with BIM for project-wide visibility. Benchmarking Comparing performance against industry standards. • Uses metrics like cost/m², time/ft² vs. benchmarks. • Identifies gaps, targeting 10-15% improvements. • Annual reviews for portfolio-wide lean maturity. Artboard 3 Lean Construction Infographic © 2025 Protrain — Licensed under CC BY 4.0. Complied by Ashutosh Maurya.