For centuries, technological advances have allowed the construction industry to develop stronger, cheaper and more durable building materials. These days, factors like sustainability, transportability and functionality are driving manufacturers to create innovative building materials. Imagine an office building whose exterior can clean the air around it or sidewalks that repair themselves when they are cracked. What if windows could regulate carbon dioxide in a room or insulation that better regulates temperatures to reduce heating and cooling costs?
While architects and owners are typically the decision makers as far as what materials are used in construction, contractors are the ones responsible for working with them. Today we’re going to look at some innovative building materials that are currently being researched and developed that will shape the design and construction of future buildings.
Building Integrated Photovoltaics
Harnessing the power of the sun and converting it into electricity is no longer relegated to bulky solar panels mounted on frames on top of buildings. Photovoltaic cells are being incorporated into curtain walls, skylights, canopies and building façades. Solar cells are also being utilized in roofing materials from shingles and roof tiles to walkable flat roofs. See-through glass with a sprayed on organic solar cells are being developed that not only generates electricity from sunlight but also from artificial light sources. While building integrated photovoltaics (BIPV) are less efficient than traditional solar panels due largely to the fact that panels can be angled for optimal performance, BIPVs are more aesthetically appealing and can be assimilated into multiple areas of a building.
A large amount of research on self-healing concrete is being performed around the world. Various methods are being tested but most involve imbedding the concrete with a substance so that when the concrete cracks it is released and reacts with either the material in the concrete or the carbon dioxide and moisture in the atmosphere to form a substance that fills the crack and hardens. These substances range from bacteria spores to glass capillaries filled with a healing agent to a microencapsulated sodium silicate. Engineered cementitious composite or bendable concrete involves replacing the larger material in concrete like sand and gravel with specially coated reinforcing fibers allowing it be ductile when strained. When this material is strained it creates multiple micro cracks as opposed to one large crack which are then repaired when it reacts with water and carbon dioxide to form calcium carbonate.
More than Just a Window
So what will the windows of tomorrow be able to do other than generate electricity as mentioned earlier? Kinetic glass is being developed that could regulate air quality in a room by opening tiny slits or gills to allow in fresh oxygen when carbon dioxide levels reach a predetermined amount in a room. This is accomplished by embedding Dynalloy Flexinol wires in cast silicone. When the sensors detect a need to regulate the air quality they send an electrical charge through the wires causing the gills to open or close. Another technology being developed for commercial use is electrochromic glass which allows windows to go from transparent to opaque with the flick of a switch. The glass contains material that can change color when a low voltage of electricity is passed through it by creating a chemical reaction that changes the way it reflects and absorbs light. Once the change occurs it will remain that way until the polarity is reversed causing the window to become transparent once again. This technology could reduce heating and cooling costs by allowing more light in on cooler days and blocking it on hotter days. It would also eliminate the need for blinds or shades.
Electro Conductive Gypsum Board
Imagine never having to search around for an available electrical outlet to charge your cellphone or plug in your laptop. Created by Eric Olsen of Superficial Studio, gypsum board is integrated with flat-wire technology and could one day eliminate the need for conventional outlets. This product could also reduce energy consumption by providing just enough electricity to power the device. The one downside I see to this technology is the amount of patching the end user will have to do once they’ve finished plugging all their gadgets into every available square inch of wallboard.
Building a Better Brick
The humble brick has been used as a construction material for thousands of years which are commonly kiln-fired clay blocks. Some university researchers have developed a brick that is reportedly 37% stronger than regular unfired bricks. Clay soil is mixed with sheep’s wool and alginate, a natural polymer found in seaweed, and then allowed to dry and harden without needing to be kiln-fired. Another method being developed to eliminate the need for carbon dioxide producing kiln-fired brick involves adding a combination of bacteria, urea and calcium chloride to sand to create a chemical reaction that hardens the brick. These bio-engineered bricks could also eliminate the need for mortar as they continue to bind together after the brick has hardened. Depending on their composition they can be as strong as marble once hardened. Although the downsides to both of these technologies is that they take longer to harden than kiln-fired bricks and the bio-engineered bricks release a large amount of ammonia that is converted into nitrates in the hardening process that could contaminate groundwater.
Temperature Regulating Insulation
Typical building insulation works on the principal of slowing the transfer of heat whether it is from reducing the amount of heat leaving a building on cold days or the amount entering it on hot days. Phase change materials have the ability to absorb excess heat when temperatures are too hot and then release that heat when temperatures are too cold. In addition to being incorporated into insulation, phase change materials are also being integrated into windows and wallboard products. Phase change materials can be integrated into existing building and can drastically reduce heating and cooling costs.
The science behind a self-cleaning building involves applying a photo catalytic material such as titanium dioxide to the exterior of building material. When the material is exposed to sunlight it creates a chemical reaction that speeds up oxidation which breaks down organic material on the building’s surface as well as pollutants in the air surrounding the building such as nitrogen oxide. Everything is then washed away the next time it rains. It essentially creates a building that not only cleans itself but also the air around it. This technology has currently been applied to concrete roofing tiles and exterior aluminum façade panels.
Some of the products mentioned are already widely commercially available and others are just now making their way onto the market while others are still being researched and developed and won’t be available for a few years. As the demand for more sustainable, technologically advanced and environmentally friendly building materials increase, manufacturers will continue striving to produce solutions that are cost effective and provide improved functionality. Until that day comes I’ll just have to continue closing the blinds on my window and plugging my desk fan into an electrical outlet when my office gets too hot.