Modular construction offers a high-quality, fast delivery option to help meet Scotland’s homebuilding targets, says Andrew Daly, Head of Architectural Services at Graham + Sibbald.
Over 100,000 new homes need to be built over the next decade to meet Scotland’s housing needs. They need to be energy efficient to help tackle climate change and a significant percentage need to be at the affordable end of the market.
One potential option is provided by modular construction. In this approach, new homes are pre-fabricated in a factory as a series of sections or modules. These are then delivered to the construction site for assembly. In many ways, modular homes are the construction equivalent of IKEA furniture.
One of the strengths of this approach is its speed of construction, which cannot be beaten using traditional building techniques. It is possible to manufacture the main elements of a modular home in less than a week and to put a home up not long after.
Such rapid construction is possible due to the highly efficient and controlled production line used to make the modules. Fast on-site construction speeds are possible due to detailed pre-planning and design process, all geared to maximise the potential of factory off-site construction. The modular approach also removes a lot of the unknowns that can hamper the progress of a build, such as bad weather and workmanship issues.
Modular construction usually features the production of highly insulated, timber frame panels. This means that it can deliver ‘low carbon’ homes that are cheap to run, provided they are augmented with more sustainable heating systems such as ground / air-source heat pumps or PV solar panels.
Among the drawbacks of the modular approach is its perceived lack of flexibility. There are only so many ways to build modules within a factory environment, due to constraints with factory size and the machinery used in the factory, and due to the logistics of the delivery of the modules. In comparison, on a traditional build there are many ways to design houses, with no module constraints to think about. In addition, most current housing developments feature a large variety of house types. It would be difficult to provide this variety using modular build, without incurring significant cost and time increases.
The modular approach also imposes specific constraints due to the logistics of delivery. Pre-fab sections can only be so big, as they need to be transported on a wide HGV which must be able to use the existing road network and go under bridges.
Modular building also needs significant investment in terms of a factory production facilities. The companies that do it are generally very experienced and have been up and running for a long time. Start-ups would require substantial investment in facilities, machinery and skilled personnel, to be competitive with the more experienced players in the market.
When it comes to the cost of the finished product, a modular home can be cheaper than traditional methods, however, much like traditional methods, costs can vary depending on location, size, complexity and design and on how automated the construction of the modules can be.
Overall, modular building is still something of a niche approach, but it is growing in popularity. As more research and development progresses in this field, the costs to construct modular homes should get cheaper, and it should become more mainstream. It will certainly play an important part in helping deliver Scotland’s housing needs in the next decade and should see a growth in the share of the housing market it is responsible for.
The opportunities provided by modular construction will be one of the topics discussed at the upcoming Graham + Sibbald webinar on the Future of Scottish Housebuilding. It promises to be a thought provoking event that should help develop consensus and spur on positive change.
To find out more about our upcoming webinar, which will be held on Thursday 16th September, please email webinars@g-s.co.uk
