Here it is very important to understand the different requirements
of Fire safety in both these systems because of their differing
installation and application style.
In stick systems, the primary element is the façade panels which
gets attached on the exterior part of the wall by leaving an air gap
for insulation purpose of the inside occupancy. The façade panels in
stick systems exist in a range of configurations and often combustible.
Therefore, NFPA 285 (“Standard Fire Test Method for Evaluation
of Fire Propagation Characteristics of Exterior Wall Assemblies
Containing Combustible Components”) standard was formed to test
and evaluate the combustibility of such exterior assemblies.
Whereas in the unitized system, façade systems are fixed to a
bracket extending outwards from the floor assembly. This often
leaves a gap between the floor and façade panels which often
ranges from 50 mm to 200 or 250 mm.
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