Modular construction 101: here’s how it’s making buildings sustainable

Posted on: 15 November, 2023

Modular construction isn’t just another design fad – it’s a growing trend with huge potential to help us realise a sustainable built environment.

Construction is under greater pressure than ever before to become more sustainable. The impact of the built environment on greenhouse gas emissions is well documented, with our sector responsible for around 25% of the UK’s annual emissions. What’s more, the construction industry produced over 10 million metric tons of carbon dioxide in 2021, which accounted for 2.4% of the total UK carbon emissions for that year.

Yet the demand for new buildings isn’t slowing down. By 2060, the global building floor area is expected to double, and ten years before that, the energy demand from the built environment may have grown by another 50%.

Unsurprisingly, work is being done to look for new alternatives to the traditional construction lifecycle and implement new, sustainable processes. One such process that may hold a lot of promise for helping realise a sustainable built environment is modular construction.

What is modular construction?

Modular construction is where buildings are made of repeated and standardised sections, known as ‘modules’. While it is technically a form of prefabrication, this modern method of construction focuses on building large and repeated sections, whereas prefabrication is reserved for specific components and materials.

As with prefabricated buildings, modules are constructed in an off-site factory setting under controlled conditions, away from the site of the project itself. The vast majority of the work is completed in this environment before the modules are transported to the site for assembly, and all work still conforms with modern building codes, regulations and standards.

Learn more: A guide to prefabrication (and how it’s transforming construction)

Modular buildings are a fast-growing market. Imports of prefabricated structures or modular units have doubled in the UK since 2019. A 2021 report by Savills found that 10% of new homes being built involve modular construction methods, while the US market for this sector is expected to grow to as much as US$271billion by the end of the decade.

8 benefits of modular construction

1. Greater sustainability

Modular structures offer significant opportunities for improved sustainability. As the market for modular construction projects grows, specialist builders are utilising sustainable construction methods to reduce the embodied carbon of the materials used. Many companies are also focusing on energy efficient design practices when constructing modular units.

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

2. Reduces material waste

Factories that construct modules are often more controlled environments than those on-site, allowing them to both better ensure quality of building components and modules and, most importantly, reduce the amount of wastage created in production.

3. Potential for reuse

Modular buildings are designed with recycling in mind and have high potential for reuse and repurposing as they’re often portable, versatile and flexible by nature. This is another win for sustainability, as businesses and construction companies have the option to reuse existing modular buildings instead of creating new ones and producing more carbon emissions.

Learn more: What is adaptive reuse (and how can it create a sustainable built environment)?

4. Speed of production

Perhaps the most immediate benefit modular construction for businesses over traditional methods is the acceleration of production. Modular projects can be completed 30-50% faster, owing to their standardised and repeated design and the fact their production takes place off-site, meaning it doesn’t clash or interfere with other processes.

5. Cost-effectiveness

As modular buildings are oriented around repeated designs, the cost of producing these can often be cheaper than having pieces built separately. What’s more, as these projects have a faster turnaround time, they reduce the number of working hours required and, subsequently, labour costs. And, with a lack of skilled personnel a key challenge for companies (more so than even rising building material costs), this could be a particularly important benefit for the built environment.

Learn more: All buildings great and small: the spectacular rise of tiny homes

6. Aesthetic and design opportunities

Along with being practical and efficient, modular buildings hold possibilities for more attractive and eye-catching design.

The Nakagin Capsule Tower in Tokyo, Japan (pictured) is perhaps one of the most famous examples of modular design, dating back to 1972, and while it is now no longer standing, many of its component units have been successfully repurposed.

7. Protection from weather

As with prefabricated construction, modules that are built in factories rather than on the building site are protected from the weather, ensuring greater quality control and preventing delays or potential issues with assembly.

Learn more: Building climate resilience into the built environment

8. Improved health and safety

Protection from weather won’t just benefit the final product – it will keep workers safe, too. Shorter turnaround times decrease the risk of adverse weather and, subsequently, injuries to staff.

The potential drawbacks of modular construction

It’s important to note that modular construction isn’t without its potential drawbacks and challenges.

Less variety

The repeated designs of modular construction will likely be appealing to many, but it can pose challenges from an architectural standpoint. Modular construction works best when modules are produced at scale, which naturally means businesses will be left with limited variety, as attempts to differentiate them defeat the benefits of this approach in the first place.

Transportation costs

Like prefabricated buildings, there are cost-savings when it comes to off-site construction, but transportation can still pose a financial headache. This is especially true of modular construction, which are even more at the mercy of traffic, height restrictions and road widths, owning to their large size.

The modular approach is more than just another trend – it’s an innovative and sustainable alternative to traditional construction methods that could go a long way to addressing our sector’s impact on the ongoing climate crisis. What’s more, if business can make it work for their construction projects, they will experience a raft of other operational benefits, too.

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