In recent years, the technology of three-dimensional printing, which is constantly evolving, is increasingly oriented towards the construction of buildings. One of the largest printing plants in the world is called Big Delta, it is entirely made in Italy and was installed in Ravenna.
With a height of 12 meters, it is capable of making low-cost buildings using low-quality materials, such as mud. It costs between 40 and 50 thousand euros and is aimed at companies and craftsmen in the construction sector who intend to open up to the world of 3D printing in the coming years.
It is part of a project designed by the company WASP (World’s Advanced Saving Project), which has been working for years on the study of a construction system capable of reducing costs and speeding up the time needed to construct buildings.
THE WASP PROJECT
The project was indeed born in 2012 and continued in stages until September 2015, to develop a printer capable of working on long cycles and with short interruptions.
The goal of reducing costs is also pursued by using poor materials available at zero mile, such as mud, clay and straw.
But one feature that sets Big Delta apart from other similar machines is its energy efficiency. In fact, the 3D printer requires about 100 watts of electricity to operate, much less than a regular household oven, and can also be powered by a photovoltaic panel.
So WASP is pursuing the goal of making a home easily accessible to everyone, and it’s doing so by putting the proceeds from the sale of the three-dimensional printers into play. 3D printing is based on the deposition of materials, which is why composite materials are the most suitable products.
The advantage of the Italian research, however, is that it uses materials available locally, at km 0 therefore, allowing to reduce costs further.
WASP printers use extruders for fluid-dense paste, where the change of state (from fluid to solid), occurs through the evaporation of a solvent that can have a different nature and in many cases is simply water.
This results in a virtually infinite combination of usable materials, which differ according to the purpose for which they are to be printed.
RESEARCH INTO NATURAL MATERIALS
At some point, however, the company moved beyond the logic of plastics to natural, readily available products that do not require chemical components and have a low impact on the environment. The research was of course carried out in collaboration with experts in the field of ecological construction.
This is why the use of hemp, a vegetable that does not require special attention for its cultivation and whose yield is about one ton per hectare, was considered. The WASP uses it as a staple fiber to be inserted into the dough.
Clay, on the other hand, is a material that has a very old tradition in the construction industry, but with 3D printing, it can be used, reducing the need for labor to almost zero. Currently, in order to prevent the clay from shrinking and drying out, the insertion of seeds of certain grasses in the printing mixture is being studied.
The first prototype of a building printed with this machine was presented at Expo 2015 and was represented by a self-sufficient unit, consisting of the house with a vertical cultivation system and a shelter for animals, all using earth, straw and some lime.
A small real estate unit can be built in 24 hours, so the printer could be used to give emergency shelter to people in areas affected by natural disasters, also because the machine can be easily dismantled and moved from one place to another.