Fire retardant lacquers only protect the surface and not the core of a panel or a rib. For acoustic panels, the FR lacquer should be added after perforating thousands of holes per m², but still the lacquer will never properly cover the inside if the acoustic holes, resulting in a finally non-approved solution. Additional lacquering with FR lacquers on the building site, for example after cutting operations, can not be validated and not be included in a Declaration of Performance. When acoustic panels are installed with a void, also the backside of the panels must be FR lacquered.
Fire retardant lacquers need to be applied in relatively thick layers to achieve the approved protection and in combination with the fact that FR lacquers must contain salts, they can not be 100% clear, resulting in a aesthetically non attractive product.