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INNOVATIONS: PRESENT&FUTURE
Intumescent Coatings Can Meet Demanding Aesthetic and Safety Standards Ronnie Peskens PPG Protective and Marine Coatings - Amsterdam, The Netherlands ronnie.peskens@ppg.com
A new generation of waterborne fire protective coatings for structural steel can address green building needs and speed up on-site and in-shop applications, writes Ronnie Peskens, Global Product Manager Fire Protection, PPG Protective and Marine Coatings
T
he use of exposed steelwork, both internally and externally, has grown rapidly over the last 20 years as architects have implemented
modern design principles with a strong focus on aesthetics. Structural steel is no longer hidden behind walls and ceilings but has become a part of everyday life. Open office plans feature circular columns and air-conditioning systems which run though cellular beams. Sports arenas make extensive use of curved trusses in roof assemblies, which are considered an architectural feature. In summary, exposed steelwork can be used to create an identity to a building and to a business. These changes in building design have had a knock-on effect to the process of passive fire protection (PFP). Traditional PFP systems, including cementitious spray and fire resistant boards, have seen increasing levels of competition from intumescent coatings. Cementitious sprays, although considered a cost-effective solution, are usually applied in very high thicknesses. This adds substantial weight to the structure and may even require the use of thicker steel. The risk of corrosion underneath the cement and the difficulty of repairing subsequent damage, have been a source of major concern in recent years. Moreover, these kinds of sprays deliver very rough finish standards, which are often not acceptable to designers. The installation of boards on the other hand is a high cost process, which requires specialist skilled labour. Even though boards provide a highly efficient thermal barrier, the lack of pre-fabricated shapes for complex structures limits their use to standard beams and columns. Intumescent coatings are designed to expand at high temperatures, from a very thin, lightweight film into a thick foam-like layer that forms an insulation char to protect the steel. They offer an aesthetically pleasing,
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N.33 - 2020 APRIL - ipcmÂŽ Protective Coatings