Insulation’s impact on fire resistance: What to consider

by Tania Wannenburg
Insulations impact on fire

Lafarge explains the importance of fire-resistant systems in buildings as fire rated ceilings & partitioning systems are of vital importance for evacuating inhabitants in case of fire.


While the primary purpose of fire resistance in any building is protecting human lives, the cost of the physical damage that can be incurred should also be taken into consideration. Replacing buildings is costly, and fire safety must take all aspects into account.

Fire resistance in ceiling products requires special attention as a ceiling structure collapsing in the event of a fire will injure anyone below it. Jean-Paul Croze, managing director of Lafarge Gypsum South Africa, says it is critical to ensure that support elements are within recommended specifications to prevent broken pieces from falling down and injuring anyone.

“For the purposes of human safety and insurance company requirements, most construction projects are now compliant over and above the minimum requirements of the National Building Regulations,” says Croze.

Fire resistance with regards to non-load-bearing and load-bearing walls and floors should also be a key focus point for designers, architects, specifiers and builders. “The load-bearing components include the protection of steel columns and frames,” adds Croze.

Fire safety regulations have the following underlying purposes:
• SANS 10177: Part II: To allow people to evacuate safely from buildings, which relates to the time in the fire resistance tests in building regulations.
• SANS 10177: Part III: To prevent the spread of flame, which is covered by the spread of flame test in building regulations.
• Non-combustibility tests (SANS 10177-Part V) and the fire resistance tests (SANS 10177: Part II): Prevention of excessive generation of smoke and heat, as well as ignition, as these will affect the safe evacuation of people from buildings.

Global leader Lafarge has independently tested wall systems and Fire Rational Designs on ceiling systems that provide 30, 60 and 120 minutes of fire resistance, in accordance with SANS 10400: Parts A and T: South African National Building Regulations.

Global leader Lafarge has independently tested wall  systems and Fire Rational Designs on ceiling systems that provide 30, 60 and 120 minutes of fire resistance, in accordance with SANS 10400: Parts A and T: South African National Building Regulations.

Why light-weight steel frame (LWSF) and cladding needs to be insulated

Light-weight steel systems with cladding also need to be insulated. If these building materials reach 385oC, they will soften and start to lose strength and hence load-bearing ability. This is why insulation becomes a critical part of the planning and construction process. The insulative property of the system is also of key importance in preventing surfaces of wall cladding that are not burning, from reaching temperatures that could burn anyone touching them.

“Lafarge systems are also designed to reduce the incidence of cracking, where flames, smoke and toxic gases can seep through to adjacent rooms and cause a fire to spread, resulting in possible loss of life,” says Croze.

Lafarge Plasterboard, which is the first locally manufactured plasterboard in South Africa with an Ecospecifier listing, is designed for internal walling and ceiling solutions in both residential and commercial buildings. The plasterboard is durable as well as easy to install and it is also SABS-approved, under SANS 266.

Lafarge Plasterboard ranges from basic to high-end systems. It is used for domestic and commercial ceiling and partitioning applications. It’s also used to create bulkheads, curved ceilings and curved walls. Plasterboard is naturally fire resistant and the core slows down the spread of fire by releasing chemically-bound water when heated (this process is similar to evaporation and aids cooling).

Lafarge Fire Check Plasterboard, which is differentiated by its pink paper liner, is classified as a technical plasterboard and as a Fire Rated Plasterboard in accordance with SANS 266. Its composition is manufactured to enhance and meet particular environmental design, performance and functional requirements. Its core adhesive properties are also checked at temperatures of 970 +40oC.

It has exfoliated vermiculite and fibreglass strands in the gypsum core to increase fire resistance. Available in 12,5mm and 15mm thicknesses, this product should be used for areas where additional fire resistance is required, such as kitchens, record and filing rooms, fire escapes and specified office partitions.

Croze explains that Lafarge understands the challenges faced by the building industry to measure up to the SANS 10400-XA energy efficiency legislation. “It is for this reason that we want to provide solutions as close to specification requirements as possible to give architects and interior designers the flexibility to adapt design concepts without compromising the environment,” concludes Croze.

Lafarge Gypsum
Tel: 011 389 4500
Website: www.lafarge.co.za

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