2.2.3 Construction materials, classifications of reaction to fire as per EN 13501-1, except floors

Table 4: Classification of reaction to fire as per EN 13501-1

Construction material class	Smoke generation	Dripping behaviour	Comment	Example
A1			Organic portion≤ 1 %	Concrete, stone, metal, plaster
A2	s1	d0	Bulk density ≥ 600 kg / m3 Paper weight ≤ 220 g / m3	Plasterboard t ≥ 9.5 mm
B	s1 s2 s1 s1/ s2	d0 d0 d0 d0	Bulk density ≥ 1000 kg/m3	HPL-Compact FR thickness ≥ 6 mm Composite elements consisting of HPL FR bonded to flame-retardant wood substrate, e. g. cement-bonded chipboard t ≥ 10 mm or flame-retardant chipboard t ≥ 12 mm
C	s2	d0		HPL-Compact FR t < 6 mm HPL-Compact sheet standard t < 8 mm Composite elements consisting of HPL FR bonded to flame-retardant wood substrate
D	s2	d0	Substrate ≥ 12 mm Bulk density ≥ 600 kg / m3 Bulk density ≥ 400 kg/ m3 Bulk density ≥ 400 kg/ m3	HPL-Compact standard t ≥ 6 mm Composite elements consisting of HPL type S/P bonded to standard wood substrate, e. g. plywood t ≥ 9 mm or solid wood t ≥ 12 mm
F				(LDF) Low density fibre board
F			No requirements defined	Some plastics

A rear-ventilated facade made of fire retardant HPL-panels as cladding can therefore be considered as a safe facade solution in terms of fire properties described under the following conditions:

strict observance of and adherence to the relevant European, national and local regulations
the system built on the site has to correspond strictly to the products tested and classified which means for example the use of non-combustible mineral wool insulation.
Further important parameters are the subconstruction, the dimension of the rear-ventilation air gap, the use of horizontal fire barriers, etc.

When designing and building facades these details have to be considered – built as tested! The person in charge of the building planning is responsible for the correct tender. HPL-panels have to be subjected to a continuous quality control according to EN 438 including the reaction-to-fire performance.