3D printing in the construction industry
The construction industry is one of the sectors that is resilient to sustainability requirements. This is mainly due to the fast-track nature of the project and the contractor's preference to adopt conventional methods, resulting in controlled planning, and faster work programming but, in turn, in a high amount of waste. Add to this the heavy equipment required for each phase of the project, dispersing high amounts of CO2 into the external environments.
Engines during enabling works
The 3D printing technology is an innovative technique, relying on a laser machine that transforms a liquid resin into a durable strong material through an additive process of layers one above the other, capable of withstanding the different loads of gravity, temperature, wind, and seismic actions where applicable.
Laser machine and process of adding resin layers
Pros and cons of the 3D printing industry
Like any new technology, 3D printing has its pros and cons, which are summarised below:
Create complex geometries
Faster design to construction time
Minimised to zero mistakes
Increased safety on site
Materials and energy saving in construction
No local materials available
Very high cost of imported materials
Limited availability of local 3D printers
Yet to be codified for structural uses
3D printing and sustainability
3D printing can be an effective sustainable solution due to the following criteria:
Reduction of material waste by using only the required number of materials.
Elimination of on-site fabrication, thus eliminating transportation costs which are considered the largest contributor to CO2 emissions.
Substitution of cement with an alternative material. We note that cement is responsible for almost a 10th of the world's industrial water use, often in water-stressed areas, and that its production involves quarrying, which causes air pollution by creating dust, exacerbating respiratory diseases. Moreover, gravel extraction and production usually require explosives which is detrimental to the environment.
However, the biggest challenge of 3D printing is its high cost and lack of regulation, which makes this technology unreliable from a client's perspective.
Many operational and research improvements still need to take place before 3D printing will be considered by today’s clients, engineers, and contractors.
What can we do now?
There are several ways to promote sustainable construction through the implementation of some processes:
Cutting materials precisely to reduce waste.
Controlling waste management, such as separating and recycling waste.
Adopting more restrictive code approaches and establishing KPIs to be monitored and controlled at each stage of construction.
Emphasizing green buildings’ concept and construction.
Adaptive reuse projects that transform old buildings.
Treating water on site, recycling food containers, etc.
Selecting sustainable and recycled materials.
Promoting circularity of materials and their selection.
Projects using 3D printing
The 3D printing is an innovative technique that still needs some improvement in order to become popular among construction contractors. The time delay will depend on several factors, especially governmental actions and regulations regarding CO2 emissions applicable to all sectors and industries. Until then, simple daily measures should be forced on the construction sites and people dedicated to the supervision of these measures should be hired, hence developing environmental awareness for all categories of people.