nd it’s a good thing. Because the next generation has been weaned on digital technology. The Millennials, who by 2030 will constitute 75 percent of the workforce in the U.S., will shun careers in construction or manufacturing—unless those careers become an extension of their techno-centric, eco-conscious world view. And the need for highly skilled construction experts is about to explode, as flight from the suburbs into urban areas accelerates. In Houston, for example, more than 5,000 units of residential apartments are breaking ground right now—and Houston is a city with only 3,500 full-time residents in its downtown core. To get a better sense of how this transference will play out over the next century, let’s focus on the construction industry. Get ready for a wild ride.
Infrastructure: What’s Old Is New Again
Entropy happens. But what if instead of tearing up old bridge pilings, or tossing 100-year-old house framing into a landfill, we reuse these materials in brand new products? I’m not talking about repurposing salvaged stuff. That’s always the best environmental choice, sure, but not everything has salvage value for new construction. Who wants to deal with dusty wall insulation from the 1950s, for example? New technology, however, might give that stuff—along with crumbling drywall, concrete rubble and even rusty nails—a chance to start over.
We’re not there yet, but nanotechnology is pointing in the direction of breaking materials down to their molecular (or smaller) levels and reusing them. And as if by magic, 3D printers are exploding as a new technology. They’re going to need lots of raw material to build new objects.
Innovation has already expanded the lifespans of many common building products. Here are just a few examples
Epoxy Grouts Two-part products resist mold, have greater strength and generally do not depend on regular homeowner maintenance. Newer products such as PROMA’s PRO GROUT EXTREME (shown) contain no VOCs and claim the same low maintenance as epoxies.
Cementitious Tile Backers
Remember when drywall was installed behind tile showers? It’s no wonder showers were among the shortest-lived components of a new home. New cement-based underlayments, such as CertainTeed’s BackerBoard product, contain about 25 percent recycled material, and last for decades.
With a lifespan of up to 50,000 hours, an LED bulb outshines all previous technologies (except possibly sodium lamps). It also contains no mercury.
A clay, concrete or metal roof should last at least a century. The old 15-lb. felt underlayments, however, tended to fail after less than 20 years. New high-tech, rubberized and self-sealing products promise to at least double the tenure of a good roof material.
For example, in the near future, EWP producers may want to know if sections of century-old wood framing can or should be re-incorporated into sheathing panels as raw wood fibers. A little digging turned up a report from Sweden (http://bit.ly/T4PQyz) on wood structures, which found that wood retains its integrity for millennia: “Under dry conditions, the effects of age on wood structure appear minimal up to an age of 4,400 years.” This suggests that wood fiber from deconstruction could be reincorporated into new materials almost indefinitely. Use of salvage wood for that purpose is cost-prohibitive for now, but that could change as the massive reconstruction of the ‘burbs accelerates.
As research on nanobots proceeds, researchers are experimenting with simpler techniques of nanoengineering, such as bonding extremely small particles chemically with other materials. But even this advanced chemistry has its limitations.
For example, concrete suppliers have been testing various recycled aggregates for many years. One goal is to include more recycled materials, such as tire rubber or asphalt from roof shingles. But when, for example, they try mixing recycled tire rubber in concrete, they find that the additive only improves heat transfer when the mix is less than 5 percent rubber in the mix. Add any more rubber, and heat transfer actually increases. This is because the tiny particles in the recycled rubber reduce air space in the concrete (source: Excellence in Concrete Construction Through Innovation). This makes the material better suited for road use in cold climates, where surface freezing is a problem, but less attractive for green building.
It’s likely, however, that such simple “mix and test” approaches to materials could become less definitive, as nanotechnology improves. It’s conceivable that nanobots added to the mix could “adjust” spacing between materials, vastly improving a material’s energy performance.
The End of Physical Labor
Building is “dirty, dangerous and dull” work. It’s increasingly tough to find laborers willing to do the backbreaking work of framing, tiling, roofing, erecting and dismantling scaffolds and trusses. But this hands-on tradition may fade away in coming years.
If you visit a steel-forming plant in Japan, you don’t see grimy, haggard looking workmen covered with blackened hands and clothes like you do at many plants and distribution centers in the U.S. You see men and women in white lab coats, behind glass, operating remote machinery with digital screens and interfaces.
There’s actually a term now for controlling robots with virtual reality technology: tele-operation control system of construction robot, or TCSCR. This technology is closer to field-ready than you might think. A century of tinkering with automated equipment in manufacturing—especially the auto industry—has created a vast body of work on robotics. And I’ve seen modern, autonomous robots at work in building product factories as well, including one on a visit to Ireland a couple of years ago that could pick up extremely fragile evacuated solar tubes and move them around at post-human speed.
But the Holy Grail of robotics is a synthesis of human control with robotic magnification of those assets. For example, the science of “haptics” refers to conveying our sense of touch to a machine. Tests of human control of robots using joysticks and servo valves were already underway at least a decade ago. It’s likely that VR control will continue to improve, become more precise, more “real” to the controller—and more fun (thus more attractive to Millennial workers).
One obstacle to virtual reality’s viability has been computing power, but that roadblock is fading, as Moore’s Law continues to hold (at least for now; as Michio Kaku points out, it won’t accelerate forever).
One of the major advantages to robotic construction is design optimization. Robots have already been used to create extremely strong structures using much less raw material than their human counterparts. For example, they can create complex joinery in plywood that allows them to construct walls with compound curves unlike anything human crews can handle.
Anticipating Life Cycle Changes
Already, building science has greatly increased the maintenance for many products—with fiber-cement siding, manufactured stone, “lifetime” faucet and door hardware finishes. But we’re still a long way from a zero-maintenance structure. Many organizations are focused on establishing life-cycle assessments (LCAs) that offer real information on the environmental impact of a material or product.
That’s the right direction for today, but what if in the near future, life cycle becomes more or less meaningless, as biotechnology creates components that can literally last indefinitely, with minimal maintenance? Imagine the reduction in resource consumption if we never had to replace another asphalt shingle, repaint siding or replace the grout in a tile shower.
Of course, any durability discussion must include the realities of human behavior. People get restless, often changing their residences for personal reasons, or to accommodate changing family situations. To that end, the most durable structures of the future will need to be flexible and changeable—designed for easy disassembly and reassembly. And as I’ve written before, durability isn’t the only way to achieve environmental balance. Another approach is to create structures that are “made to degrade,” using components that can dissolve into their natural surroundings without causing harm. Here again, biotechnology might play a role—for example, by giving an entropy nudge to “behind-the-walls” mechanicals that biodegrade when exposed to sunlight, or triggered by a passcode. Appliances from a Printer? Ask any production builder: one of the biggest challenges to any construction project is managing the flow of goods and materials to the site. Price and dealer fluctuations and varied installation methods (an issue tied to labor) slow things down. Even with streamlined shipping and packaging, much of any building’s footprint lies in its use of far-flung materials. Locally sourcing materials reduces that impact, but what if the buyer wants granite countertops or Mexican tile? That’s where future generations of 3D printing may provide a solution. Right now, a 3D printer, which can create three-dimensional objects, uses spools of polymer. But future printers may be able to transform the rawest materials—cellulose fibers from old timber, raw gypsum from demo drywall or scrap metal—into new, precision engineered objects. It’s possible that 3D printing could have the same effect on the building industry that Netflix had on DVD rental chains like Blockbuster. How will a company that makes windows or vent fans or door hardware survive if every builder has a 3D printer on the job site, along with a few thousand cubic tons of raw materials, ready for conversion? The answer is simple: the company owning the brand will sell the elaborate code that the printer needs to produce a certain model of sink or faucet. Imagine something like the Kindle audiobook model, applied to product blueprints. You can download a blueprint license for a certain number of sinks or toilets before it self-destructs. Manufacturers can finally leave behind the industrial age, and enter the knowledge-based economy. GB
Can we survive the hive?.
Biotech believers are giddy about nanotechnology. But before we rip the lid off Pandora’s Box, some very serious ethical and risk factors need to be addressed. That’s because once we have the power to manipulate objects at the molecular (or smaller) level, we could easily get into trouble. For example, tiny bots might be programmed to carry out a specific function, such as converting suspended plastic molecules in the ocean into biodegradable material, or they might remain inside concrete wall assemblies, with the sole purpose of repairing cracks and other degradation. But what if nanobots become sophisticated enough to mutate or multiply, and attack the wrong molecules, destroying or transforming other life forms or ecosystems? Clearly, before scientists pursue this technology blindly, worldwide scrutiny and guidelines must be put in place. The prospect of godlike power over the building blocks of matter is tantalizing, to be sure, but let’s make sure the cost is not too high.