The same may not be true of buildings, however, if an
article that turned up on the Wall Street Journal site last week is correct.
According to the article, a Chinese firm called Winsun had developed what
appears to be a very large version of a 3-D printer; one with nozzles that
spray concrete instead of ink or sugars (or whatever), and which uses glass
fibers for reinforcement. Using this giant printer, the company was able to
pre-assemble enough parts to build 10 houses of 200 square meters each (about
1,460 square feet, if I’ve done my math correctly) in only 24 hours. The
company is working on other applications for the system, including commercial
properties, office buildings and so on. So far there is no word on how long it
will take them to generate larger prefab elements, or how large a structure can
get before this method will lack the structural strength to stand on its own…
Now, we should probably note that Winsun isn’t exactly
putting a template for a house into a three-D printer and just pressing the “go”
button. What they are assembling are effectively prefabricated sections for a
building made entirely out of reinforced concrete, and there are definite
limitations to how useful an all-concrete structure is going to be for
residential/non-industrial applications. It’s also worth noting that anything
you could actually call a “house” will also require glass for the windows,
wiring for the outlets, doors that you could actually open (as opposed to ones
made exclusively out of reinforced concrete), plumbing and fixtures made out of
porcelain (or the equivalent), lighting, kitchen appliances, and a host of
furnishings. Having the structure spring up in matter of hours – or however
long it takes the concrete in the prefab sections to cure, anyway – would speed
up the process, but it is debatable how much it would lower the cost. Despite
what the article would have us believe, this is more “advanced prefab building
technique” than it is “super high-technology magic…”
On the other hand, it is hard to deny that there are lots of
useful things you can build out of reinforced concrete – and that if Winsun is
actually successful in adapting the printer to use whatever salvaged materials
come to hand in building its prefab sections, they might be able to overcome
the cost issue. You’d still need the rest of a construction company to finish
off the buildings, but there is some real potential here. And if someone
applies the same technology to other building materials (there are already
smaller printers that work with composite laminates, for example) there doesn’t
appear to be any reason why you couldn’t fabricate all of your building
components this way. Maybe we should keep an eye on this story going forward…