What is lean construction (and why should you adopt it)?

Posted on: 22 April, 2024

When applied to the construction industry, the lean methodology can help businesses reduce waste while maximising cost and resource efficiency.

The construction industry is facing a conundrum. As a consumer of over 40% of the world’s resources and a creator of over a third of global waste, the construction process is often at direct odds with the push to sustainability. But with three-quarters of the infrastructure that will exist in 2050 yet to be built, sustainability skills in short supply and the demand for homes and buildings rising in line with a growing population, our sector simply doesn’t have the opportunity to slow down. A survey of construction professionals found that 85% had experienced delays in major projects, all leading to additional costs and longer delivery times.

Sustainable innovations and initiatives are emerging – the likes of heat pumps, adaptive reuse and retrofitting are helping to both optimise operational energy consumption and provide alternatives to the environmentally damaging process of demolition, but alone they aren’t enough. As a key contributor to embodied carbon emissions, the built environment needs to pay particular attention to the pre-operational construction process.

Learn more: What is embodied carbon (and what can we do about it)?

In an effort to increase sustainability and reduce waste, the lean production methodology, which dates back to the early 1900s, has been adopted by the construction industry to great success.

Lean construction, defined

Lean construction is an integrated project delivery process that seeks to emphasise collaboration between teams and maximise stakeholder value. Derived from lean production, the ultimate goal of this relationship-based approach to construction is to increase the profit, innovation and productivity resulting from a project.

The lean philosophy has its origins in the work of Henry Ford and the production of the Ford Model T in the early 1900s, but it was pioneered most notably by Toyota and their famously efficient production system after the Second World War.

The success of the likes of Toyota led to lean production being adopted in other capacities, with the construction industry just one of many to replicate this approach. Lean practices have also been adopted by companies across industries like retail, printing and customer service.

What are the six lean construction principles?

There are six core principles of the lean construction model:

Identifying value

While traditional approaches to construction seek to satisfy the requirements of the customer as per their plans and specifications, lean construction digs deeper into the reasoning and rationale of the project and unites the perspectives of all stakeholders involved under common goals. In simple terms, it goes beyond just delivering the specification – it also seeks to deliver the value and provide the service and advice necessary throughout the project.

Mapping the value stream

Once again, lean construction places significant emphasis on the value of a project. The purpose of this lean principle is to ensure that value is clear for all involved – throughout every stage and process of the project. This is known as a value stream and is an essential component of lean thinking.

Creating flow

In the lean construction model, ‘flow’ is defined as how work progresses through a system – i.e., do projects move consistently from one task to another without interruption or delays, or are there starts and stops in the process? Flow can be positive and negative, with the aim being for work to progress through each stage as smoothly as possible. It can be impacted by both physical and intangible factors, as well as external and internal influences.

Using a pull system

‘Pull’ systems are used in the lean construction philosophy to link output and production to customer need and eliminate the creation of waste. It works on the principle that, if it hasn’t been requested downstream by the customer, it shouldn’t be produced by anyone upstream.

Reducing waste of materials and productivity

As a methodology centred around efficiency, one of the primary goals of lean construction is the reduction or elimination of waste.

As we’ve previously mentioned, the built environment is a major contributor to global waste. Adopting lean construction principles will help companies reduce the following types of waste:

  • Overproduction and underproduction
  • Defective materials and components
  • Unnecessary transportation
  • Materials that aren’t immediately required

Along with physical and environmental waste, lean also considers wastes in efficiency and working hours by minimising:

  • Delays and waiting times
  • Overprocessing and unnecessary features

Continuous improvement

While the above principles can have a huge impact on an organisation’s operations, productivity and profit, they’ll be ineffectual if they’re not consistently applied and implemented throughout a firm’s corporate culture.

Lean is not static – to make it a success will require constant and continuous monitoring and implementation to identify opportunities for improvement. It’s a never-ending process, and learnings from all experiences are applied to future projects to optimise performance and encourage continuous improvement.

Why should businesses adopt lean construction?

1. Improve site safety

Construction is, by nature, an industry with significant health and safety risks. While awareness and training have improved in recent years, there are still, on average, 61,000 non-fatal injuries to construction workers ever year. And while the fatal injury rate for the sector is 1.62 per 100,000 workers, this is still four times higher than the overall rate across all industries.

As a methodology centred around clear communication and coordination, lean construction can significantly improve the onsite safety of employees by creating a safer work environment. By engaging stakeholders, encouraging monitoring and promoting risk management, adopting a lean approach can help construction firms keep their workers safer.

2. Reduced cost of projects

Through the lean principles of flow, pull and waste reduction, lean construction can reduce the underlying costs of a construction team’s projects.

By improving flow, construction companies can prevent delays – and thus extended project costs for management, workers, etc. – in their project. What’s more, pull ensures there’s no overproduction, and that only the materials and components required as created and transported to the site.

3. Improved sustainability

Adopting lean construction practices can help the industry address its role on the climate crisis, too. Reducing wastage is a central principle to lean construction, and the focus on improving collaboration, continuously monitoring for opportunities to improve and only producing what is required will help reduce the environmental damage caused by an organisation’s construction project.

Learn more: Making a business case for sustainability: why now is the time to act

4. Higher quality output

Through great efficiency, reduced overproduction and optimised, continuous workflows, lean thinking can help improve the overall quality of a firm’s output, from the materials and components all the way to the final finished product.

5. Better project management

Along with the challenge of delays and the pressure to become more sustainable, the biggest challenges facing construction teams include materials shortages and a lack of appropriate skills and expertise. Luckily, these are all things that the lean construction model can help mediate through improved project management. With more efficient communication between parties, along with greater monitoring and a pull approach to resources, lean construction can reduce scheduling conflicts and boost productivity and efficiency.

Learn more: Diagnosing the green skills gap: what skills is the built environment missing?

6. Faster project turnarounds

Time is expensive, and in a construction project, it can create a multitude of problems – not least of which being added expense. By promoting greater collaboration between stakeholders and focusing on an efficient approach that minimises construction waste, the lean approach can help project teams reduce construction times and turn their projects around faster.

7. Improved customer and employee satisfaction

As emphasised in the principles of value and the value stream, the outcome for the customer and all stakeholders is central to successful adoption of the lean construction model. Working closely with customers and stakeholders helps ensure the projects is achievable and meets their expectations. It’ll also keep them on time and on budget – something which will satisfy all stakeholders.

It’s not just customers and stakeholders who stand to benefit from the lean method – employees involved in the project will have a better experience, too, thanks to improved health and safety and a reduction of project delays.

Sustainability isn’t a passing trend – it’s here to stay and is constantly evolving. If you want to inspire and action change in your career, UCEM’s MSc Innovation in Sustainable Built Environments will give you the skills you need, both now and in the future.

Find out more: MSc Innovation in Sustainable Built Environments – University College of Estate Management