Whilst modular construction is well-established, 3D printing is in its infancy. Some construction experts say that in future a hybrid approach will offer significant economies of scale
The use of 3D printing (3DP) technology on the construction site is expected to grow in the coming years. A report released by Research and Markets last year forecast that globally, the sector would be worth almost $1.6bn by 2024, up from $3m in 2019. The rapid rise gives a clear signal that the technology’s time is coming, as it is increasingly slated for use in projects around the world.
Its increased use is being watched carefully by the modular construction sector, as the combination of the two technologies will offer huge benefits within the built environment, both financially and in terms of time, materials usage and labour needs. Modular construction itself is enjoying a period of growth. It eclipses the 3DP market, albeit now with a lower annual growth due to its greater maturity. By 2026, the market globally is expected to reach $107bn, rising from a market size of $65bn in 2018.
Whilst some industry watchers have asked if 3DP will be able to compete with modular construction in the near future, others are looking at the economies of scale that would come from merging the technologies and using a hybrid approach to modular construction. Hybrid approaches to 3DP and modular design would combine the advantages of off-site construction with those of digital fabrication and scale/volume.
“Will full-scale 3D printing ever compete with modular printing? 3D printing can replace modular construction when it can add value. The problem for modular construction is repetition of production. When templates are being used to mass produce units, it does not allow for diversity. If diversity is required, then 3D printing can add value, for example in cost and time,” said Zhu Jianchao, Vice President & Chief Engineer, China State Construction Engineering Corporation, during the Construction Technology Forum in Dubai.
3DP can replace or integrate with modular construction where it can add value, such as with repetitive production tasks where some diversity is required. When templates are used to mass-produce units, it does not allow for diversity. If diversity is required, then 3D printing can add value, for example in cost and time.
This is where the hybrid element could have a key advantage, because one of the limitations of 3DP today is that it is an on-site technology. Using it off-site for modular components could be executed quickly, with minimal materials waste. It would mean 3D printing a module rather than assembling it in pre-cast, for instance, building all bathrooms for a job in a factory, and then transporting it to the site as a module. The obvious downside is this would increase transport miles and associated emissions.