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The new classification system for the reaction to fire performance of building products in Europe has been applied to five different product families of wood: Wood-based panels, Structural timber, Glued laminated timber, Solid wood panelling and cladding and Wood flooring as being ‘products with known and stable fire performance’. The European classification system includes two sub-systems, one main system for all construction products except floorings and the other for flooring products. Wood properties such as density, thickness, joints and types of end use application including different substrates have been studied thoroughly and are included in the classification. Most wood products fall in classes D-s2, d0 or Dfl-s1 (for floorings). Testing has been performed according to EN 13823 (2002) SBI- Single Burning Item test, EN ISO 9239-1 (2002) Radiant panel test, and EN ISO 11925-2 (2002) Small flame test. In all, more than one hundred wood products in different end use applications have been studied. Clear relationships between the main Euroclass fire performance parameters and product parameters (such as density and thickness) have been demonstrated. Tables with reaction to fire classification of different wood products and end use applications have been developed, approved by the European Commission and published in their Official Journal. This procedure is ongoing with further official decisions to be published. The new classification system for the reaction to fire performance of building products in Europe has been applied to five different product families of wood: Wood-based panels, Structural timber, Glued laminated timber, Solid wood panelling and cladding and Wood flooring as being ‘products with known and stable fire performance’. The European classification system includes two sub-systems, one main system for all construction products except floorings and the other for flooring products. Wood properties such as density, thickness, joints and types of end use application including different substrates have been studied thoroughly and are included in the classification. Most wood products fall in classes D-s2, d0 or Dfl-s1 (for floorings). Testing has been performed according to EN 13823 (2002) SBI- Single Burning Item test, EN ISO 9239-1 (2002) Radiant panel test, and EN ISO 11925-2 (2002) Small flame test. In all, more than one hundred wood products in different end use applications have been studied. Clear relationships between the main Euroclass fire performance parameters and product parameters (such as density and thickness) have been demonstrated. Tables with reaction to fire classification of different wood products and end use applications have been developed, approved by the European Commission and published in their Official Journal. This procedure is ongoing with further official decisions to be published.

Fire retardants may considerably improve the fire properties of wood products, but the durability, e.g. in exterior applications, has not been addressed fully. This paper reviews the existing knowledge and experience mainly from the USA with the aim of supporting further development in Europe. The review is concentrated on pressure impregnated fire retardant treated wood products which have the best opportunities for increased durability. Copyright © 2001 by John Wiley & Sons, Ltd.

Fire retardants may considerably improve the fire properties of wood products, but the durability, e.g. in exterior applications, has not been addressed fully. This paper reviews the existing knowledge and experience mainly from the USA with the aim of supporting further development in Europe. The review is concentrated on pressure impregnated fire retardant treated wood products which have the best opportunities for increased durability. Copyright © 2001 by John Wiley & Sons, Ltd.

Cone calorimeter tests were performed on specimens made of pieces of wood and pieces of gypsum plasterboards protecting the wood against the heat. The thermal behaviour of the gypsum plasterboards of different origin was studied by determining the time to onset of charring and the charring rate of wood. The specimens were exposed to a constant heat flux of 50 kW/m². The test results show that the time to onset of charring is more dependent on the board thickness than the area weight of the boards. The charring rate is fairly well predicted both by the board thickness and area weight, the latter being slightly better as a prediction parameter. The mechanical board properties needed in order to fully understand the fire protection from gypsum plasterboards were not studied in this investigation. Copyright © 1999 John Wiley & Sons Ltd.

Cone calorimeter tests were performed on specimens made of pieces of wood and pieces of gypsum plasterboards protecting the wood against the heat. The thermal behaviour of the gypsum plasterboards of different origin was studied by determining the time to onset of charring and the charring rate of wood. The specimens were exposed to a constant heat flux of 50 kW/m2. The test results show that the time to onset of charring is more dependent on the board thickness than the area weight of the boards. The charring rate is fairly well predicted both by the board thickness and area weight, the latter being slightly better as a prediction parameter. The mechanical board properties needed in order to fully understand the fire protection from gypsum plasterboards were not studied in this investigation. Copyright © 1999 John Wiley & Sons Ltd.

The charring of wood studs has been studied in the cone calorimeter at constant heat flux 50 kW/m² and compared to data from full-scale furnace wall tests. The wood studs were unprotected or protected by gypsum plasterboards on the exposed side. Similar charring depths were found and the data analysed mainly in terms of fire exposure. A simple small-scale technique was developed to measure the heat transfer through protective boards and the charring depth of wood studs. These properties are essential for the load bearing capacity of wood frame structures. © 1998 John Wiley & Sons, Ltd.

Two types of fire retardant insulating wood-fiber boards have been developed in laboratory and mill scale. Both include treatments which are incorporated in the normal wet process for manufacturing such boards with a concentration of the fire retardant to one side of the board. One type involves addition of a calcium borate mineral, colemanite, to the top fiber layer of the board. Scandinavian class II and British class 1 are achieved. The other type involves addition of a pre-condensate of melamine-dicyandiamide-phosphoric acid mixed with a commercial phosporus-nitrogen compound on the wet lap. Scandinavian class I and British class 1 are achieved. The first type, colemanite, creates no problem in normal board production or in respect to product properties. It is readily suited to full scale application. The second type has a better fire classification but is accompanied by production and product problems, e.g. mildew growth at humid exposure, and needs further development.Both board types have been exposed in ceiling application for 8 years without any reduction in fire classification.

The charring of wood studs has been studied in the cone calorimeter at constant heat flux 50 kW/m2and compared to data from full‐scale furnace wall tests. The wood studs were unprotected or protected by gypsum plasterboards on the exposed side. Similar charring depths were found and the data analysed mainly in terms of fire exposure. A simple small‐scale technique was developed to measure the heat transfer through protective boards and the charring depth of wood studs. These properties are essential for the load bearing capacity of wood frame structures. © 1998 John Wiley & Sons, Ltd.

Abstract: The equilibrium tensile properties of urea-formaldehyde (UF)- and phenol-formaldehyde (PF)-bonded particle boards have been studied at moisture contents between 1 and 33% and at temperatures between −15C and +45C. These conditions may occur e.g. during exterior use of the boards. The tensile strength and the modulus of elasticity decrease slightly while the strain at rupture increases slightly between 1% and 7% moisture content. These effects are similar for UF- and PF-bonded boards. Above 7% moisture content the tensile strength and the modulus of elasticity decrease markedly while the stretch at rupture increases with increasing moisture content. These changes are more pronounced for UF-bonded boards. The bending stiffness is less affected than the modulus of elasticity since the board thickness increases with increasing moisture content. The tensile properties are not significantly affected by the temperature at low moisture contents, but at high moisture contents the combined effects are more pronounced. The effect of moisture is generally stronger than that of temperature, in the range studied.