Often described as a solution to the housing crisis, off-site construction has continued to evolve slowly. Will we see a significant shift in attitude and a broader practical application of these techniques by the larger construction firms? Dave Howell reports.

Will modular off-site fabrication become a critical component of the construction industry? Two years ago, the HoUSe project from Urban Splash, developments such as the Apex House in Wembley (a 29-storey building constructed with self-supporting modules), Dalston Lane, Hackney and the Greystar development in Croydon illustrated what can be achieved with off-site fabrication.

Christy Hayes, CEO of Tide Construction Ltd, said: “Building high-quality homes faster, and with less disruption to the local area, is of paramount importance in such a fast-evolving area of south London. Modular construction is highly suited to rental developments as investors and operators can welcome residents into their homes sooner and open the revenue streams earlier”.

The use of off-site construction continues to be niche yet has the potential to become a vital component of all construction projects, from domestic homes to wider infrastructure projects. The chronic housing shortage that has dogged successive governments could be eased by off-site construction, which could reduce build times and costs. The construction industry would do well to be open to the possibilities that off-site construction could deliver.

Recently published, a report from the House of Lords concluded that the future of all construction would contain some form of off-site fabrication if more support across the entire supply chain can be developed.

Eugene Lynch, Managing Director of The McAvoy Group, said: "The construction industry faces significant challenges: low productivity, poor performance, inconsistent delivery on time and on budget, a growing shortage of key skills and a lack of transparency relating to issues such as life cycle costing and project performance. We believe these issues can be addressed with the wider adoption of off-site construction technology, provided the barriers to change can be removed. We look forward to the Government’s response to this visionary and extremely well-informed report”.

Modular future

To gain an insight into the current state of, and potential for, off-site construction, Croner-i spoke with Tim Hall, Director, Buildoffsite.

Can you point to any projects that illustrate that pre-fabricated off-site construction methods are the future of construction?

"Up until five years ago, most of the traditional house builders were pushing back on the off-site model, stating that it would never work at scale”, Hall commented. "However, within the Tier 1 sector, there were some that had more of a future-facing attitude. Around two years ago, we had what some had described as a perfect storm that consisted of a looming skills shortage, the continuing chronic shortage of homes and the issues around Brexit.

"Also, I think terminology needs to be used carefully. For many in the industry, the term pre-fabricated creates an image of a 1940s low cost and low-quality building. Also, using a phrase such as ‘modern methods of construction' can also be misleading when you look at off-site timber frame construction. Many in the industry will react by saying that the timber frame isn't a modern method, so you have to be careful with the terminology you use when discussing off-site construction.

"The approach is horses-for-courses. This field is nothing if not flexible. You can, for instance, decide whether you crane in a fully-fitted out kitchen or bathroom, which then just need connecting up — which, of course, can be done without the need for highly-skilled workers. You have to think about what you want to achieve and how off-site construction can help you meet your goals for the project. The issue is that the construction companies that can see the value of off-site and want to use this is perhaps just 10% of the whole industry.”

Is more education about the benefits of off-site construction vital to move the industry in general to at least considering off-site as a component of their projects?

"Yes, I think that's essential. Also, we approach this via our membership. What is vital is to inspire people to make the connections themselves and not force this way of construction down their throats. They can join and learn about what is best practice.

"Around a quarter of our members are clients, with the same number coming from the supply chain. Another 25% are architects and consultants who are vital as there is no point in them designing something that can't be manufactured off-site. We encourage them to work and learn with us to make the integrated connections necessary to expand the use of off-site construction. Simple, practical elements such as designing components that are no more than 3.5m wide so they can fit onto a lorry that can drive down roads across the UK need to be communicated.”

Would legislating to force construction companies to include some form of off-site manufacture within each of their projects move the industry towards this method of construction?

"This argument has been put forward by many people — including some within our organisation. My view is that the industry as a whole needs to create a compelling proposition that is taken up by the construction companies. I don't think forcing anyone to do anything has ever resulted in the outcomes expected.

“The industry doesn’t have an appetite for more legislation. Change has to be more holistic and driven by a desire to do things differently. My ambition is for the off-site community to create products that the industry sits up and takes notice of, and wants to use, but isn’t forced to by legislation. We need to create brilliant buildings that are difficult to produce traditionally, that have high energy performance and are cheaper to build or cost the same as traditional builds.”

What does the future of off-site construction have in the broader construction industry, in your view?

"What we have seen is that significant government departments have publicly stated that, where possible, off-site construction should be used. This is clearly a mandate for the construction industry to pay more practical attention to the benefits off-site construction can offer them. This is ideal for our industry, as if a construction company continues to use traditional means of building, we can then ask where off-site fell short of their needs, which informs how we need to improve our services and fabrication systems to meet their needs.

"The last year has also seen changes simply because of Brexit. Every house builder I speak to is concerned that they just won't have the number of skilled workers they need to meet house building targets. Off-site is gaining more attention as one solution to this issue.

“Large urban developers, for instance, are looking very closely at off-site construction and are prepared to make investments into factory facilities that can fabricate the components they need. Suitable examples include student accommodation and hotels that have identical repeatable rooms, are ideal for more off-site construction.

“Also often overlooked for off-site construction are large infrastructure projects. Why not manufacture a pre-cast concrete bridge off-site for instance, which is just part of the whole off-site industry, but which could form an essential component for future infrastructure projects.

“What we are now finding is that the off-site factories are lagging behind the kind of off-site construction components that are wanted today. The market has moved on, and existing suppliers will adapt. We are seeing new entrants into the off-site market who are geared to producing new and exciting components for the construction industry to use.”

Hall concluded: "To look at numbers in the housing sector, for instance if you take out timber frame, which is at the component level, fewer than 2000 homes were built last year using an off-site solution. If you add in timber frame, this number is closer to 20,000 homes or about 10% of the market. I think in the next two years that number will grow to 20%. And it could be less than 10 years before this reaches 50% of the housing market”.

The future of prefabrication

  • The pre-conceptions associated with previous prefabrication projects are being slowly eroded as high-profile buildings in the public and private sector using off-site construction make the wider industry take notice.

  • The use of more off-site construction will continue to rise, as it is undoubtedly one component that could help relieve the shortage of housing.

  • New entrants into the off-site market are illustrating how flexible off-site can be.

Last reviewed 7 March 2019