Last edited 11 Sep 2019

How is modular construction keeping waste out of landfills?

1 Introduction
2 The advantage of modular to the environment
3 Reduce the need for demolition
4 Summary
5 Related articles on Designing Buildings Wiki

[edit] Introduction

Although modular construction can be eco-friendly, with energy-efficient build methods, there is still a need for significant commitment to the world's resources. This means keeping the materials heading to landfill to a minimum.

More than a third of all waste hitting the landfill is from the construction industry, as much construction and demolition waste is never recycled.

To put this into context, the average new-build project produces 3.9 pounds of waste per square foot. This means that new 50,000ft office block built in the centre of a town will have created almost two hundred thousand pounds of waste – or about 100 tonnes. Only about 20% of this is likely to be recycled. Ultimately, demolition will also add to this.

[edit] The advantage of modular to the environment

Modular buildings are constructed inside, along a production line similar to a factory. This has some distinct advantages, which allows for the preservation of materials. First, as the components are not exposed to the weather, the quality is retained. This reduces wastage. Second, as the units are produced again and again for clients, the supplies can be ordered in and stored onsite. This means that any left-over resources from one project can be used on subsequent modules.

Reports suggest that off-site production can reduce waste by 90%. The controlled environment not only protects against weather conditions but also site theft. As the unit is delivered 80% complete, any work done on site is finished quickly. Therefore, the chance for onsite waste to gather is limited merely by the practicalities of time.

This is not just about the resources sent to landfill. Quicker construction times reduce the need for traffic to and from the site. Diesel fumes are a significant contributor to poor air quality. Second, the shorter construction time means energy requirements are proportionally reduced.

[edit] Reduce the need for demolition

Demolishing the a 50,000ft building creates 4,000 tonnes of waste, much of which cannot be recycled as it is contaminated with other materials. All the glass, wood, steel and other resources that could be recycled are combined with materials that are non-renewable and non-recyclable. Therefore, all this material may go to landfill.

Modular construction is premised on the environmental mantra of reduce, reuse and recycle. Much of the module unit can now be built using recycled glass, steel and wood. Any materials meant for one project do not need to be discarded; they can be reused in the next project, reducing the need for purchasing more. Then, when deconstructed, which can be done as quickly as constructed, the parts can be recycled.

In short, the significant factor for the environment and the overflowing landfill sites is that module construction is not demolished. First, the module unit can be moved. Therefore, if there is a sudden need for a different use for the land, then there is no need to knock down the building and discard it. The unit can be deconstructed and moved to the new location. Similarly, if the building is no longer needed at all, the components can be reused. This reduces the need for additional material and the energy required to buy new.

[edit] Summary

Traditional construction methods can be material- and energy-intensive. The high-energy techniques, the additional transportation needs and the potential loss and degradation of materials can all add to the cost to the planet. In contrast, modular construction can offer greener and more sustainable building practices which should be a priority for all constructors.