Self healing concrete. Carbon Nanotubes. Sweating rooftops. Some materials may sound like science fiction, yet all are currently being developed and tested in laboratories throughout the world. Despite their technological complexity, these materials may be on the market sooner, rather than later. Below are brief overviews and links to learn more.

Self-healing concrete

Scientists at the Delft University in the Netherlands are working on bacteria, that when added to concrete mixtures, "repairs" cracking.

A cross-section of self-healing concrete. (TU Delft)

Concrete is mixed with the bacteria and food which the bacteria like to eat. The bacteria is activated by water and begins to eat the food source. The result is a chemical reaction where calcium combines with oxygen and carbon dioxide to form what is, basically, limestone.

Want to learn more? http://www.citg.tudelft.nl/en/research/projects/self-healing-concrete/ 

Carbon Nanotubes (CNTs)

CNTs are tubular cylinders of carbon atoms that have extraordinary properties ranging from 200 times the strength and 5 times the elasticity of steel to 15 times the thermal conductivity of copper. Better yet, CNTs are highly resistant to environmental and physical degradation.

For example, when CNTs are added to concrete, there is no need for re-bar. This way, concrete can be formed into different shapes due to the exceptional tensile strength. Imagine the time saved during construction not having to use rebar.

Want to learn more? http://www.nanowerk.com/spotlight/spotid=25561.php 

Sweating rooftops

Poly(N-isopropylacrylamide)-referred to as PNIPAM-is a microgel polymer and is known as an intelligent soft nanomaterial. Using PNIPAM, researchers at Swiss Federal Institute of Technology in Zurich have developed a type of matting that is used on rooftops to extract heat.

PNIPAM roof mat. (Rotzetter ACC)

When it rains, the PNIPAM matting soaks up water like a sponge. In sunshine, the matting releases the moisture on its surface where it evaporates. The matting operates similarly to how people perspire, moisture evaporates in an effort to move heat away from the body. Also, the matting is just millimeters thick and can save up to sixty percent in air-conditioning costs during the summer months.

Want to learn more? http://www.wired.co.uk/news/archive/2012-10/03/sweating-buildings-cool-down