Robot revolution: Dutch prefab firm steals march on the UK

“Construction is the last major undisrupted industry on the planet.”

Construction News is in Amsterdam, sitting with Voorbij Prefab chief executive Jos Mulkens.

“I believe companies like Apple and Google really see the size of the opportunities in our sector, and I’m convinced they’re looking at it already,” he adds.

Voorbij Prefab is in the business of offsite manufacturing, making precast concrete elements for houses.

But this company doesn’t work like others you may know. It used to make heavy losses and was on its knees three years ago before Mr Mulkens took over and turned it upside down, completely changing its approach.

Mr Mulkens is an evangelist for the power of technology to improve construction – and believes he is seizing an opportunity to disrupt the construction industry and radically change how it operates, before the likes of Apple and Google get there first.

Ray’s way?

Here in the UK, Ray O’Rourke has been the most vocal proponent for the offsite approach.

He has long believed that design for manufacture and assembly is the only way forward for the industry in the long term, especially if it is to get anywhere near making the cost and time savings laid out in the Construction 2025 industrial strategy.

The approach has not been cheap or without its problems for Laing O’Rourke, though. It blamed a £53m loss in 2014/15 on “cost inflation and delays” to three UK DfMA contracts.

“I believe companies like Apple and Google really see the size of the opportunities in our sector, and I’m convinced they’re looking at it already”

Jos Mulkens, Voorbij Prefab

Elsewhere, Legal & General has stated its intent to become a major player in offsite housebuilding by launching the largest modular homes factory in the world at a site near Leeds, at a cost of £55m.

It’s understood that this is just the first step for L&G, with up to £500m set to be invested in a series of facilities.

But in Amsterdam, Voorbij Prefab is already making it work – and in some style.

The company’s offsite manufacturing facility is located around 12 km north-west of old Amsterdam, on industrial land in the city’s Westpoort district adjacent to the North Sea Canal.

The Voorbij Group dates back to 1935 and was a family-owned business. It initially worked in steel reinforcement and wooden piling before moving into concrete, producing reinforced concrete piles and prefabricated concrete elements.

The Voorbij family sold the group to the Dutch construction and infrastructure company TBI in 1996, which demerged it in 2008, giving birth to Voorbij Prefab as a separate entity.

As recently as three years ago, Voorbij Prefab employed 180 people and worked in a diverse range of sectors, producing precast concrete elements for houses, offices, tunnels, bridges, industrial buildings, sound barriers and much more.

Now the company is firmly focused on housing and has fewer than 40 employees, with only 12 of those on the production line. It assembles houses on site for clients as well as supplying the elements for contractors to assemble themselves.

“We say this should be normal. We changed the mindset by getting sexy for our clients”

Jos Mulkens, Voorbij Prefab

Mr Mulkens explains the rationale behind its move: “In 2013, the company was almost dead,” he says. “I went back to the shareholders and I told them we had three choices. They could wrap up the company and give up. We could go on like we were and make losses every year.

“Or you can invest one last time and see where it leads us.”

This investment involved changing the mindset of the company’s employees and revolutionising the manufacturing process.

Mr Mulkens illustrates this with another anecdote: “I said to [our shareholders] that in two years you’ll have only three employees and one dog: one employee who has experience playing with Minecraft, another employee who’s a technical guy to keep the robotics high performing, and one guy to feed the dog.

“And the dog has to be very aggressive to keep people away from the robotics.”

The Minecraft player would have an understanding of design, able to manipulate architectural models and add value to them before feeding them into the system, while the technical expert would keep the robotics in the factory running.

While he exaggerates slightly, that’s effectively all the company needs.

Robots and design

Mr Mulkens and his team developed a business plan in a few weeks before being given the green light by shareholders to put it into action.

The factory was completely revamped within nine months and its output has risen from producing precast elements for 200 homes a year to around 2,000, with plenty of spare capacity still to be used. Preparation time from design to the start of manufacture has fallen from five weeks to five days.

And most strikingly of all, the time taken to prepare a mould for casting has been cut from two days to just six minutes on average, accurate down to 0.5 mm.

The elements come with structural rebar included, as well as door and window frames, plumbing and M&E services.

Previously, the design for rebar placement went out to external consultants. Regulations govern how much rebar is needed – but each consultant would design its placement in a different way.

“We still have someone pouring the concrete in, as we think a machine still doesn’t have the same ability to detect the quality of the concrete and the amount that’s needed”

Jeroen Pat, TBI

When a change was needed, Voorbij Prefab asked these consultants to each design rebar for the same element before getting them to present it to each other.

“They all presented something different, within the same government regulations,” says Jeroen Pat who works for TBI, Voorbij Prefab’s parent company, and has been working closely with Mr Mulkens on the transformation taking place in Amsterdam.

“They had the same tools and the same skills, but their mindsets were completely different. We asked them what was really needed to meet the regulations – and the strange thing is, [the amount of rebar] got less and less. A lot of people have a comfort zone of doing it one way and nothing else.”

Now Voorbij Prefab designs the elements in a 3D model, using plans sent to it by customers, with an engineer feeding the requirements into the model to generate the optimum solution for each element. This is then fed directly onto the production line.

On the line, a succession of robots first prepare the mould for casting, using high-powered magnets. A worker on the line then fills in any small gaps at the joints of the metal mould.

This makes sure all the elements are fully customisable at short notice, combating one of the traditional criticisms that offsite manufacturing is too rigid and inflexible if design changes are needed.

Another machine then welds together steel rebar before it is lifted into place on the element. As we walk around the factory, one whole section of the building lies empty except for this welding machine – previously there were 40 welders here and now there are none.

The final stage sees concrete poured into the mould – with a human still carrying out this work.

“We still have someone pouring the concrete in, as we think a machine still doesn’t have the same ability to detect the quality of the concrete and the amount that’s needed,” Mr Pat says.

Normal lean

The technical side is all very impressive, but is perhaps not far beyond what Laing O’Rourke has achieved in Worksop and what L&G plans to do at its new facility.

The difference, Mr Mulkens says, is mindset.

“Anybody can buy the tools if you have the money. You can train your people to get the skills, or you can hire some new people who are much better educated. But you have to work on the mindset.”

He goes on to say that lean manufacturing, often touted as something construction should learn from the automotive industry, is “basic”.

“Anybody can buy the tools if you have the money. You can train your people to get the skills. But you have to work on the mindset”

Jos Mulkens, Voorbij Prefab

“We say this should be normal – if you don’t manage this [correctly], you don’t have a position anywhere,” he says. “We changed the mindset by getting sexy for our clients.

“Before there was no focus on the market and our employees were really unmotivated. But now, next week 40 people will come here for the first time to see how their houses are produced. The guys who work here have never seen these people before, so it’s also for them.”

Central to all of this is a willingness to experiment and make mistakes, as long as employees keep learning. “Making [faulty] elements is not a problem, but it shouldn’t happen the second time,” Mr Pat says.

“It’s a culture where you can learn and adapt and go further. The factory has changed from three months ago – and in three months it will be different again.”

Wrapped up in this change were the aforementioned job cuts, which did hit a lot of people hard.

Mr Mulkens concedes that this was difficult. “It’s not easy to do that,” he says. “But we have found new jobs for some of them, or managed to get some others to retirement.”

He isn’t willing to go into much more detail than this. Mr Pat, however, says the firm believes that, overall, the approach has created more jobs than it has eliminated. “With more elements, more logistics are needed. There are more truck drivers, and more guys on site assembling – we made 200 houses a year before, now we make 1,600 or more.”

Cloud construction

Mr Mulkens also declines to discuss the level of investment required for all of this. It’s clear that it was a sizeable sum – but he insists that “we don’t like to speak about money”. He does say that the factory makes a profit now having made a loss before, and that a return on investment will take five years.

The grand vision is for Voorbij Prefab to be at the centre of a global supply chain of similar facilities, partnering with companies in other countries that perhaps work in other sectors.

“If Laing O’Rourke has a very good factory, we can send them the information over to run it wisely”

Jos Mulkens, Voorbij Prefab

“We see it as a 3D printer, not more than that,” Mr Mulkens says. “You can connect more printers to that. We narrowed down our market to housing and we’ll stay there. But how do we do more than that? Not by building a new factory next door.

“We can use our data and manage other factories from here, and we need the best partners for that. We need partners with the same kind of attitude who can think and act differently.”

What about working with the companies in the UK that are on this journey, too?

“Sure,” he says. “If Laing O’Rourke has a very good factory, we can send them the information over to run it wisely.”

Mr Mulkens is in his stride now, highlighting the differences between his company and traditional construction firms.

He rarely mentions concrete during my visit, as he points out: “An old-fashioned company speaks about cement and concrete: ‘How do we make it stronger? How do we make it flow better?’ We don’t – that’s boring. That’s almost the same for everyone.”

He also mentions risk and how it dominates the thinking of your average contractor – and how this presents an opportunity the world’s big tech companies are eyeing with interest, just as the likes of Uber and Airbnb have disrupted the taxi and hotels industries before them.

“If others don’t follow they will be Ubered – or, as we say, they will be Voorbijed”

Jos Mulkens, Voorbij Prefab

“The traditional industry is so conservative and they are risk-averse; we need to show them how it works,” he says.

“Construction companies are all about mitigating risk. They always ask, ‘Who has the risk and how can I manage it?’ We have to be open and share.

“If others don’t follow they will be Ubered – or, as we say, they will be Voorbijed.”

Several European contractors were set to visit the factory this year to see how it works in real life, with Mr Mulkens revealing that a number of major firms, including many that work in the UK, are inviting him to present on his company’s transformation and the new culture he has instilled.

He finishes with one question, which is directed at the industry as whole: “We believe in this. We are really proud about what we do because we’ve seen what it’s done already.

“Would you like to join us, or not?”