FACTORY FRESH FUTURES : SCIENCE & TECHNOLOGY

 

Three dimensional printing and construction : Factory Fresh. Your next home could emerge from a printer.

A batch of new houses across California is selling unusually fast. In the past two months, 82 have been snapped up, and the waiting list is 1,000 long. 

That demand should, though, soon be satisfied - for, while it can take weeks and months to put up a conventional bricks-and-mortal dwelling, Palari Homes and Mighty Buildings, the collaborators behind these houses, are able to erect  one in less than 24 hours.

They can do it so rapidly because their products are assembled from components prefabricated in a factory. This is not, in itself, a new idea. But the components involved are made in an unusual way : they are printed.

Three-dimensional [3D] printing has been around since the early 1980s, but is now gathering steam.

It is already employed to make things ranging from orthopedic implants to components for aircraft. The details vary according to products and processes involved, but the underlying principle is the same.

A layer of material is laid down and somehow fixed in place. Then another is put on top of it. Then another. Then another. By varying the shape, and sometimes the composition of each layer, objects can be crafted that would be difficult or impossible to produce with conventional techniques.

On top of this, unlike conventional manufacturing processes, no material is wasted.

Just press ''print''

In the case of Palari Homes and Mighty Buildings, the printers are rather larger than those required for artificial knees and wing tips, and the materials somewhat cruder. But the principle is the same.

Nozzles extrude a paste [ in this case a composite ] which is then cured and hardened by ultraviolet light.

That allows Mighty Buildings to print parts such as eaves and ceilings without the need for supporting moulds - as well as simpler things like walls. These are then put together on site and attached to a permanent foundation by Palari Homes construction workers.

Not only does 3D-printing allow greater versatility and faster construction, it also promises lower cost and in a more environmentally friendly approach than is possible at present.

That may make it a useful answer to two challenges now facing the world : a shortage of housing and climate change.

About 1.6 billion people - more than 20% of Earth's population - lack adequate accommodation. And the construction industry is responsible for 11% of the world's man-made carbon-dioxide emissions.

Yet the industry's carbon footprint shows no sign of shrinking.

Automation brings huge cost savings. Mighty Buildings says computerising 80% of its printing process means the firm needs only 5% of the labour that would otherwise be involved.

It has also doubled the speed of production.

The World Students Society thanks author The Economist.