Fireproofing buildingsFire-resistant coating to prevent failure in steel building fires

A few extra coats of “paint” could be all that the steel in a building needs to prevent itself from buckling and failing in a fire.

Scientists from Nanyang Technological University, Singapore (NTU Singapore) and national industrial developer JTC came up with this idea when they were figuring out a commercially viable solution to protect reinforced concrete against underground fires.

After two years of intensive research and development by the interdisciplinary team, an affordable 3-in-1 coating that offers enhanced fire and corrosion protection was invented.

Named FiroShield, the new coating is cheaper and less laborious to apply, and can function aesthetically like normal paint.

Existing steel structures in buildings are usually coated with a fire-retardant layer to shield the bare metal from damage by fire and meet the fire protection standard of two hours – aimed at giving occupants enough time to evacuate the building. Today’s conventional intumescent coatings are thick, more expensive and laborious to apply.

NTU says that in contrast, this made-in-Singapore coating can be applied on bare steel without the need for sand blasting to prepare the surface and will protect the material against fire for two hours without falling off. The overall coating time can hence be reduced by half as compared to conventional coatings which translates to lesser man-hours required. FiroShield has also been tested on other construction materials, such as reinforced concrete and laminated timber, and has the same excellent performance.

To achieve a two-hour fire rating, FiroShield requires just five layers of coating, compared to conventional coatings, which requires up to 15 layers or more. It is thus two times faster to apply and is cheaper by about 50 percent due to its lower materials cost and manpower requirements.

In addition to its fire-resistant properties and easy application, FiroShield can also protect the steel surface from corrosion, which no other fire coatings in the market can do at the moment.

FiroShield is expected to last longer when exposed to weathering elements such as moisture and ultraviolet rays. Its performance barely dipped by two percent, as compared to the drop of up to 75 percent for conventional coatings when subjected to weathering tests in the lab. This will reduce the maintenance cost and frequency of inspections over the lifespan of a building.

Leading the research team is Assistant Professor Aravind Dasari from the School of Materials Science and Engineering and Professor Tan Kang Hai from the School of Civil and Environmental Engineering.