You take a risk not using non-combustible solutions
The Grenfell tower disaster is one of the latest examples showing that combustible materials, for which the fire safety characteristics have been improved by adding fire retardants, are not always a safe choice. Below we compare the most common types of wood panelling for walls and ceilings in public spaces. The comparison is both for the core materials themselves and for the final solutions including veneer, lacquer, perforations and making linear ribs.
Fibre Gypsum
The core
Fiber gypsum contains 83%, or more, non-combustible minerals and is classified A1-S1,d0 or A2-S1,d0. No impregnating chemicals or fire-retardant lacquers need to be used.
The panel or rib as a whole
Gustafs wooden panels with a fire gypsum core hold class A2-S1,d0, including the lacquer and acoustic perforations. Gustafs ribs hold a rock-hard B-s1,d0.
MDF
The core
FR-MDF, improved with fire retardants and with class B-s1,d0 are available.
The panel or rib as a whole
With additional veneer, FR-MDF drops to fire class C or lower. Additional FR-Lacquers can be used, but the salts and thicknesses required, make them non-clear. Perforated holes cannot be lacquered. MDF is normally only tested as a board, not as a linear rib.
Plywood
The core
Plywood can be impregnated and improved to class B-s1,d0. The impregnation and drying process can lead to warping panels or ribs.
The panel or rib as a whole
Impregnations cannot pass the glue layers in the plywood and acoustic perforations might expose non-impregnated material. Ask especially if the top veneer is included in the certification. Plywood is normally only tested as a board, not as a linear rib.
Solid Wood
The core
Solid wood can be impregnated to B-s1,d0, although only few suppliers have certificates for all wood species and length/width dimensions. The impregnation and drying process can lead to warping panels or ribs.
The panel or rib as a whole
Solid wood can be impregnated to B-s1,d0, but lacquers must be added afterwards. Fire classifications do seldom include the surface finish like lacquer, oil or stain. Linear solutions with small width dimensions are seldom included in the certification.