Where would we be without our warm houses, coffee shops and offices? We rely so heavily on buildings and infrastructure in our daily lives that the construction industry uses around 400 million tonnes of material every year. Ithas been estimated that around 30% of materials on site during construction endup as waste.
UK company Biohm has developed a technology that allows buildings to be built and dismantled easily and for the components to be reused. This innovative system, called Triagomy, consists of modular pieces that can be used in different combinations to achieve virtually any design. It can be assembled without a binder, making it easy to substitute or reuse in other compatible buildings. Triagomy is made of bio-based materials produced from other industries such as agricultural waste.
Many other companies in the UK and elsewhere - Sika, Ideal Modular Homes and Ilke Homes - are attempting to address the issue of sustainable building through the exploration of modular construction techniques.
Modular building attempts to produce and assemble at least 80% of the building in the factory and build foundations on site. This allows for much safer and faster construction rates and a reduced need for design as houses can be mass produced with room for customisation.
This construction technique has the advantage in that it happens in a controlled factory environment leading to a significant cut in waste. A study done by the Waste and Resources Action Program says that building offsite leads to waste production of 1.8% of all the materials used in the construction phase, against the 30% generated by traditional building.
Since the process happens in a controlled environment it is easier to keep the amount of energy used during assembly to a minimum. For example, modular buildings can have deliveries to sites reduced by 90%.
Constructing modular homes has the advantage of making piece substitution easier and more efficient, in terms of waste production and costs. If the building becomes obsolete it’s much easier to recover prefabricated parts and put them to use elsewhere. Modular homes are pivotal in what concerns waste reduction and efficient use of materials.
Equally, they are more energy efficient. A study by Kim et al. showed that the operational energy consumption of modular buildings was 5% less than traditional ones. This is due to several factors, one of which is that sustainability analysis are hard and time consuming to perform on traditional building designs. When design time is reduced, more environmental analysis and performance simulations can be performed, and national requirements can be exceeded.
Lastly, production in a controlled environment as opposed to an outdoor construction site allows for more testing and evaluations to be performed during the process, which leads to a higher quality product. Modules designed for mass production can continuously be improved, adapted and pushed out on a large scale.
Automated Modular Construction
Another interesting area is automated modular construction. US company Autovol has integrated modular construction with full robotic automation with the help of ABB Robotics. This has generated a further step towards efficiency and time/ cost reduction.
At Autovol the factory assembly is entirely carried out by robots at high quality level allowing for projects to be completed in even less time.
ABB reports in its white paper on construction that in comparison to other sectors such as automotives, the built environment has been subject to less innovation in automation and efficiency of the production chain due to the outdoor nature of the industry. Therefore, in order to take advantage of modern technologies, it is vital to challenge traditional construction by exploring practices such as automated modular building.
Canadian Intelligent City is another company successfully working with ABB integrating offsite construction and robotics. Using Canada’s vast supply of timber, they produce tall modular buildings that address both the environmental and social (in terms of housing emergency) issues the construction industry is linked to by delivering affordable buildings that require much less time than traditional on-site built projects to complete.
One issue that could arise is that materials used to create modular pieces could be of lower quality. This could lead to buildings with shorter life expectancy, raising the question of what the point of saving on waste would be if the houses last less and need to be rebuilt sooner. However, this entirely depends on design choices. Different case studies show how high quality can be achieved even when building offsite.
Modular construction has the potential to be an effective solution to problems such as waste handling and energy efficiency within the built environment. It deserves attention from the industry. In countries such as Sweden, offsite building is the norm. Around 80% of new houses are prefabricated modular buildings and according to a study by McKinsey in the UK and Europe approximately 20% of new buildings will be modular by 2030.
Resources:
The future of Real Estate is Modular - Forbes
Why hasn't modular housing taken off yet? - Environment Journal
green impact modular housing - PBC today
A review and analysis of modular construction practices - Leigh University
Moradibistouni - Evaulating sustainability of prefabrication methods in comparison with traditional methods
Molavi - a construction procurement method to achieve sustainability in modular construction