Chimneys and fireplaces are often exposed to very high temperatures. They therefore demand insulation solutions that are not only non-combustible, but which will keep their form and compression strength even at high temperatures.
The fire performance of a hollow core slab without additional fire protection is REI 30 – REI 120 depending on the slab type. The additional fire protection of the hollow core or massive concrete slab slows down the temperature rise of reinforcing steels.
When corrugated steel is used as a load-bearing structure for the roof construction and insulation is installed on top of the corrugated steel board, the temperature of the metal rises very quickly. This is why you need to take into account the insulation amount above the corrugated steel board when designing the fire protection thickness below the corrugated steel construction.
When exposed to fire, all commonly used structural materials lose some of their mechanical strength. Heavily loaded steel will lose its designed safety margin at temperature around 550°C – regardless of the grade of steel. To protect the structural steel in your building, use PAROC fire protection slabs.