Off-site housebuilding: Is modular construction the way forward?
When housing minister Gavin Barwell travelled to Liverpool to visit a social development in Belle Vale he left singing the praises of an emerging building technique.
The MP attended Liverpool Mutual Homes’ Naylorsfield Drive site where the growing discipline of off-site construction was instrumental, and is now calling for the method to go mainstream.
As this experimental branch of housebuilding gains traction, Your Move takes a closer look at off-site construction and ponders whether the future of the sector is modular.
Words by Mark Langshaw
There’s nothing especially unusual about the appearance of the 33 houses occupying Belle Vale’s Naylorsfield Drive, but delve into their origin and the innovation becomes apparent.
The ‘eco’ properties on Liverpool Mutual Homes’ (LMH) social housing development were built many miles from the scheme under specialist factory conditions and later crane-lifted into position.
Ground floors, upper storeys and roofs were constructed in sequence by Manchester-based developer Bowsall before utility services were hooked up and the interiors were fitted out.
This emerging method of building is called off-site – also known as modular – construction and it’s proving a great asset to social landlords, who are under constant pressure to deliver high quality, best value housing quickly.
It may sound unorthodox but off-site construction is believed to have benefits over traditional housebuilding, such as reduced wastage, a streamlined supply chain, lesser reliance on traditional skills and swifter completion time as work under factory conditions is not hampered by variables like bad weather.
The £3.5 million Belle Vale scheme is thought to be one of the largest of its kind in Britain and LMH claims the modular building method shaved an estimated six months off development.
“It was faster than traditional housebuilding and it helped us get rent in quicker,” Ben Seabrook, assistant development officer for new business at LMH, tells Your Move. “That’s the key for us as a housing association. There’s always a housing demand out there – as soon as we hand over the property with the contractor there’s often somebody moving in that same day.
“You will get some bigger housebuilders that can complete construction quickly but this requires flooding the site with a lot of manpower. With the off-site method you don’t need to do that as everything comes pre-built – it’s just a case of piecing things together.”
Housing minister Gavin Barwell added his voice to calls for off-site housebuilding to become mainstream after visiting the Naylorsfield Drive site, but how viable is this notion?
According to Ben, the speedy completion rates off-site construction offers give it potential beyond the social sector and he has identified the first-time buyers market as a future area of impact.
“The speed of this method makes it a good fit for social housing, but it could also benefit first-time buyers by giving them the option to move into their new home within six months of construction commencing.”
“There’s definitely scope for off-site housebuilding to become mainstream,” he says. “The speed of this method makes it a good fit for social housing, but it could also benefit first-time buyers by giving them the option to move into their new home within six months of construction commencing.”
In 2004, industry-wide group Buildoffsite was formed to champion modular techniques in the UK construction sector and encourage their widespread adoption.
Speaking to Your Move, the group’s chairman Andy Dix claims mainstream housebuilders across the industry could be forced to up their investment in modular techniques to counter challenges such as labour shortages and securing building materials within tight deadlines.
“PRS (private rented sector) clients and social housing providers are attracted to the benefits of off-site construction methods,” he says. “Volume housebuilders build out low rise schemes only in response to sales and are therefore less likely to see massive benefits from the productivity gains that off-site can enable.
“However, problems in ensuring the on-time delivery of commodity materials such as bricks and blocks coupled with increasing difficulties in obtaining and retaining good quality labour are requiring almost all major housebuilders to make increased use of off-site methods.”
Indeed, there are signs that Liverpool’s leading housebuilders are dabbling in off-site techniques, with Countryside turning to factories to supplement some of its latest timber frame schemes.
Peter Vella, regional sales and marketing director at the firm, says modular elements have complemented Countryside’s timber frame output and has revealed plans to introduce more of them going forward, albeit with cautious and controlled execution.
“Factory fitted windows, insulation and pre-plastered walls are amongst changes that Countryside will be introducing but in the future we will look to do even more on the factory floor, including ready-made roofs and modular floor construction,” he tells Your Move.
“This means that the homes can remain even more air and watertight and it will also reduce the number of lorries transporting materials to the site.
“There are a lot of advances being made in timber frame construction, but as a rule we resist the temptation of introducing too many changes at once. Instead, our approach is to manage the introduction of new techniques gradually, ensuring that each one works efficiently and when it does, we will move onto the next one.”
Such positive testimonies for modular construction suggest there is scope for it to become a more prevalent discipline both here in Liverpool and further afield, but this begs the question of whether the skills and training is in place to support its expansion.
Ben Seabrook believes many of the skills taught on traditional building courses are transferable to off-site housebuilding, but points out that qualifications with a more direct focus on the technique may be needed if modular construction becomes widespread.
“At the moment people go to college and may come out to be a joiner or a bricklayer,” he explains. “Those skills can be transferred into the modular housing discipline but there would need to be courses dedicated to modular housebuilding – or at least courses with modular elements – for it to become mainstream.
“All of the people who worked on our site were general tradespeople and their skills could be transferred across, but there is the potential for colleges to one day make off-site construction a skill in itself as that may hold more appeal to some students.”
According to Andy, modular construction could fulfil its residential potential by increasing productivity in the industry if the demand for new homes and necessary funding is present.
“Housebuilders will only invest in building homes if there is a market demand and they are confident that they will be able to generate the required rate of return,” he explains.
“The most substantial area of housing need is for social housing and the challenge is really for the government to decide if it is prepared to invest the required resources to deliver the homes that are needed in the UK to avoid overcrowding and costly alternative arrangements.”
The government has promised to set out “radical” plans to boost the nation’s housing supply in its housing white paper this month, and with Gavin Barwell clearly impressed by what he saw in Belle Vale, the off-site construction advocates will be watching developments with keen interest.