Most modern structures are made of fire-resistant materials like glass, steel, and concrete. However, the process of making these materials uses a lot of carbon. Because wood from sustainably managed forests has a lower carbon footprint than steel and concrete, mass-engineered lumber offers a solution to this issue. It is the appropriate component for upcoming buildings since it enables speedier construction at cheaper costs.
Today, interior wood used in construction must be covered with fire retardant boards consisting of gypsum and magnesia or painted with a fire-retardant finish. As a result, the wood’s original grain and texture are hidden, losing their aesthetic value.
Researchers at NTU came up with a solution that coats the wood giving it the much-required fire protection, but since the coating is transparent and just 0.075 mm thick, it is invisible to the naked eye.
“Most timber or wooden panels only have a transparent coat that protects them from moisture, weather corrosion, termites or pests, and are not designed to withstand high heat,” said Aravind Dasari, Associate Professor at the NTU School of Materials Science and Engineering, where the coating was invented
“In our coating, we used technology to lock certain compounds and interact with the resin. They will actively participate in the chemical reactions in a systematic manner when exposed to high heat, thus leading to the formation of char,” he added. When exposed to fire, the coating becomes a char that is more than 30 times its original thickness. The char is engineered to be heat-resistant and insulates the wood from the high heat.
Courtesy: interestingengineering.com
One of the major problems for wood is its flammability, which is why mass engineered lumber is becoming more and more popular in the building sector due to reduced costs and quicker production. Wood or lumber can quickly burn and catch fire when left untreated. The use of fire-retardant panels or paint-like coatings that hide the wood’s natural grain is currently required to safeguard the interior of wooden buildings from fires.
In contrast, the new invisible covering lets the natural beauty of wood show through while yet having the ability to operate as a flame barrier when “activated” by fire. It is inexpensive, simple to use, efficient at stopping the spread of fire, and produces very little smoke when burned.
This incredibly transparent, 0.075 millimeter-thick fireproof coating is so thin that it cannot be seen with the unaided eye. The coating turns into a char that enlarges to more than 30 times its initial thickness when burned by a hot flame through a sequence of intricate chemical reactions. This char prevents the fire from igniting the underbrush and causing it to burn.
The made-in-NTU coating produced very little smoke during the tests conducted in accordance with industry standards and was successful in containing the flames. The fact that the wood remains intact after the char has been scraped off shows how effectively the coating protected the wood. This is significant because, in the event of a fire, construction materials must be flame-retardant and largely smoke-free to permit the secure evacuation of building occupants.