Raw OSB board

It is made with water-resistant adhesives and wood chips arranged in cross layers, which gives it properties of strength and dimensional stability similar to plywood. However, it is susceptible to moisture penetration, which can cause swelling at the edges. Despite this, OSB remains a crucial material in the construction market due to its low cost and strength.

Product

OSB (oriented strand board) is a type of composite board, in which several layers formed by wood chips or flakes are joined together, oriented in the same direction.

Gluing

It is made with water-resistant adhesives and wood chips arranged in cross layers, which gives it properties of strength and dimensional stability similar to plywood. Different types of adhesives are used, the most common being urea-formaldehyde, phenol-formaldehyde, urea-melamine-formaldehyde.

Characteristics

According to the treatments and additives to which it is subjected, OSB is classified into four groups:

• OSB 1 for interior use and decoration
• OSB 2 for load-bearing structures in dry environments
• OSB 3 for load-bearing structures in humid environments
• OSB 4 for high-performance load-bearing structures

There are two classes of potential emission of free formaldehyde (determined by EN 120 standard: drill method; ENV 717-1: chamber method and EN 717-2: gas analysis method) which are defined in the harmonized standard EN 13986:

• Class E1 £ 8mg/100g
• Class E2 > 8 to £ 30mg/100g

The uncoated OSB board produced using phenol formaldehyde glues or isocyanate resins does not require formaldehyde analysis and is automatically assigned a formaldehyde emission potential of class E1. The majority of uncoated OSB boards produced in Europe are of class E1.

Panel sizes

• Standard dimensions: 1220x 2440mm, greater than 650kg/m3
• Thicknesses: between 6 and 28mm

Product Use

• Construction and renovation