Construction and building projects often seem chaotic – delayed schedules, cost overruns, poor quality, safety issues. As an industry, construction productivity has lagged behind other sectors for decades. There has to be a better way, right?
Lean construction aims to provide that better way. It applies lean principles to the design and construction process in order to maximize value for the customer while minimizing waste. Lean construction transforms the old siloed approach into integrated teams working together toward continuous improvements.
Intrigued? Read on as we unpack what lean construction is all about!
Historical Origins of Lean Construction
Lean thinking traces its roots back to manufacturing. The Toyota Production System pioneered concepts like continuous flow and waste reduction to revolutionize automobile production. In the 1990s, some forward-thinking folks realized these same lean principles could be applied to construction projects with great success.
What were some of the main drivers for adopting lean in construction?
- Poor productivity – Since the 1960s, construction productivity declined rapidly while all other industries saw massive gains from new technology and methods.
- Project delays and cost overruns – By the 1990s, studies showed about 70% of projects were late and over budget.
- Safety issues – At the time, construction injuries and fatalities remained high at over 1000 deaths per year.
- Lack of innovation – The rigid traditional system stifled new ideas and collaboration between teams.
- Adversarial culture -finger-pointing between owners, architects, engineers and contractors was common rather than focusing on solving problems.
Several influential publications spurred the lean construction movement:
- Lauri Koskela’s 1992 paper “Application of the New Production Philosophy to Construction” challenged the prevailing construction management theories.
- Glenn Ballard’s 1994 paper “The Last Planner System” proposed new lean techniques for production planning and control.
- Koskela’s 2000 PhD thesis “An Exploration Towards a Production Theory and Its Application to Construction” examined production management theories.
A core insight was that improving production flow on the construction site holds the key to better performance. Unlike manufacturing, construction projects are unique, short-term productions. Traditional project management methods failed to properly consider production.
Lean construction emerged as a new way to manage the on-site building process, differing from the manufacturing focus of applying lean to an established production line.
Core Principles and Concepts
At its heart, lean construction aims to:
- Maximize value – Value is defined as meeting the customer’s requirements. The lean approach focuses on optimizing the whole not local efficiencies.
- Reduce waste – Waste represents any activity that does not directly add value from the customer perspective. Lean seeks to eliminate non-value adding steps.
Some key principles and concepts underpinning lean construction include:
- Improving flow – Smoothing work flow with less variability reduces waste. The goal is continuous work between trades.
- Early involvement – Involving trade partners and key project members early in the design stage improves constructability and collaboration.
- Continuous improvement (kaizen) – The lean mentality is that there is always a better way. Lean spurs innovation by empowering frontline workers to suggest improvements.
- Transparency & shared goals – Aligning commercial terms and creating a culture of transparency ensures the team pulls together.
In terms of lean techniques and tools, construction leverages concepts like:
- Last Planner System – This collaborative planning system produces predictable work flow and rapid learning.
- Visual management – Displays like task boards, schedules and performance charts provide real-time visibility.
- 5S – This method organizes the workspace efficiently for improved productivity and quality.
Lean thinking in construction differs significantly from traditional project management:
- Lean focuses on managing variability and interactions between activities while traditional PM does not.
- Lean aims to make work flow reliable rather than optimizing individual activity productivity.
- Lean sees the project as a value generation process rather than merely completing activities on time and budget.
- Lean construction integrates production management with project-level decision making.
Practical Application and Techniques
Now that we’ve covered some background and theory, let’s examine how lean construction principles are applied. Here are some key methods:
Integrated Project Delivery
Integrated Project Delivery (IPD) brings the owner, architect, contractors, and key partners together under a single contract. IPD aligns objectives and risk/reward for optimizing the overall project.
Benefits include:
- Early involvement of all parties
- Joint project validation and target setting
- Collaborative design & construction
- Shared risk and reward
- Real-time decision making
- Value focused
Studies show IPD projects experience better schedule, cost, and quality performance versus traditional delivery.
Relational Contracts
Relational contracts like Integrated Form of Agreement (IFOA) help create the culture and alignment needed for lean construction. Multi-party agreements drive collaboration and innovation rather than siloed thinking.
Job Order Contracting
Job Order Contracting (JOC) streamlines delivery by using a centralized database of pre-priced construction tasks. The owner issues job orders against this pricing catalog on an as-needed basis. JOCs enable fast-track maintenance, renovation and new construction with lean principles.
Building Information Modeling
Building Information Modeling (BIM) supports integrated lean design by enabling real-time collaboration, clash detection, and visual management. BIM models the project digitally before construction begins.
Visual Management
In lean construction, visual devices like kanban, metrics boards, safety displays and work plans provide real-time visibility and align teams. A picture is worth 1000 words.
Daily Huddles
Short daily meetings among frontline supervisors and workers help coordinate work flow between trades, identify constraints, and improve performance.
Just-In-Time Delivery
Careful logistics planning allows materials to arrive on site just as they are needed for installation. This reduces inventory waste and improves flow.
5S Workplace Organization
5S provides an organized, clean and efficient workspace to improve safety, quality and productivity. The five steps are sort, set in order, shine, standardize and sustain.
Last Planner System
Last Planner improves production planning reliability through collaborative sessions, constraint analysis and learning. Planning is a conversation, not an equation.
Implementation Challenges
Adopting lean construction involves some key challenges:
- It requires a new mindset that can run counter to ingrained practices in the industry. Silos and traditions die hard.
- Developing effective integrated contracts and relationships takes work. Most players are used to working transactionally.
- Personnel at all levels need training in lean principles and tools for successful implementation. It’s an investment.
- Securing buy-in and leadership commitment is crucial. Resistance to change and turfism can derail lean efforts.
However, the juice is worth the squeeze. Firms that embrace and stick with lean construction practices see tremendous benefits.
Benefits of Lean Construction
Here are some of the advantages that lean thinking brings to construction projects:
- Faster delivery – Studies show lean projects experience over 30% faster completion through better work flow.
- Cost savings – By reducing waste, lean methods drive 10-20% lower construction costs on average.
- Quality & rework – Defect rates may be reduced by up to 50% with lean techniques.
- Safety – Increased visualization and coordination in lean projects cut recordable incidents by 15-30%.
- Innovation – Lean unlocks creativity at all levels and encourages trying new ideas.
- Profitability – Contractors using lean practices see profit margins up to 200% higher than traditional builders.
The numbers speak for themselves – lean construction principles deliver tremendous benefits for owners, designers, contractors and society when implemented diligently. While changing ingrained practices takes work, the payoff is well worth it.
Construction projects involve complex coordination and variability. Lean thinking provides a comprehensive approach to smoother work flow and increased value. As industry pioneer Lauri Koskela stated, adopting lean construction is “the antidote to waste, variability and poor performance.”
Conclusion
The bottom line? Lean construction leverages lean principles to transform the old ways of designing and building. It brings project teams together early for smooth flow and innovation. When implemented effectively, lean methods maximize value while slashing waste in construction projects. The customer wins, the contractors win and the environment wins. While changing deep-rooted mindsets can prove challenging, the juice is worth the squeeze. Lean construction principles provide a blueprint for the future of building.