BS 300:2006 pdf download – Oriented Strand Boards (OSB) — Definitions, classification and specifications
1 Scope
This European Standard applies to Oriented Strand Boards (OSB). lt defines terms,establishes aclassification and specifies requirements.
The values listed in this European Standard relate to product properties but they are not characteristic valuesto be used in design calculations.
NOTE Test methods for determination of mechanical properties for structural purposes are given in EN 789.Determination of characteristic values of mechanical properties and density for structural purposes is given in EN 1058.Design characteristic values for OSB are given in EN 12369-1.
Information on supplementary properties is given in Annex c.
Normative references
The following referenced documents are indispensable for the application of this document.For datedreferences,only the edition cited applies. For undated references,the latest edition of the referenceddocument (including any amendments) applies.
EN 120, Wood-based panels – Determination of formaldehyde content – Extraction method called theperforator method
EN 310,Wood-based panels – Determination of modulus of elasticity in bending and of bending strengthEN 317, Particleboards and fibreboards – Determination of swelling in thickness after immersion in water
EN 318,Wood-based panels – Determination of dimensional changes associated with changes in relative hu-midity
EN 319,Particleboards and fibreboards – Determination of tensile strength perpendicular to the plane of theboard
EN 320, Fibreboards – Determination of resistance to axial withdrawal of screws
EN 321, Wood based panels – Determination of moisture resistance under cyclic test conditionsEN 322, Wood-based panels – Determination of moisture content
EN 323, Wood-based panels – Determination of density
EN 324-1, Wood-based panels – Determination of dimensions of boards – Part 1: Determination ofthickness, width and length
EN 324-2, Wood-based panels – Determination of dimension of boards – Part 2: Determination ofsquareness and edge straightness
EN 326-1, Wood-based panels – Sampling, cutting and inspection – Part 1:Sampling and cutting of test piecesand expression of test results
EN 326-2, Wood-based panels – Sampling, cutting and inspectionPart 2:Quality control in the factory
EN 326-3,Wood-based panels – Sampling,cutting and inspection – Part 3: Inspection of an isolated lot ofpanels
3 Terms and definitions
For the purposes of this document, the terms and definitions given in EN 13986:2004 and the following apply.
3.1
Oriented Strand Board (OSB)
multi-layered board mainly made from strands of wood together with a binder. The strands in the external layer are aligned and parallel to the board length or width. The strands in the internal layer or layers can be
randomly orientated or aligned, generally at right angles to the strands in the external layers
3.2
strand
piece of wood of a predetermined shape with a length of more than 50 mm and a typical thickness of less than 2 mm
3.3
major axis
direction in the plane of the board in which the bending properties have the higher values
3.4
minor axis
direction in the plane of the board at right angles to the major axis
3.5
dry conditions
conditions corresponding to service class 1 of EN 1995-1-1 which is characterised by a moisture content in the material corresponding to a temperature of 20 °C and a relative humidity of the surrounding air only exceeding 65 % for a few weeks per year
3.6
humid conditions
conditions corresponding to service class 2 of EN 1995-1-1 which is characterised by a moisture content in the material corresponding to a temperature of 20 °C and a relative humidity of the surrounding air only
exceeding 85 % for a few weeks per year
4 Classification of boards
Four types of board are classified and are distinguished as follows:
OSB/1 general purpose non load-bearing boards, and boards for interior fitments for use in dry conditions;
OSB/2 load-bearing boards for use in dry conditions;
OSB/3 load-bearing boards for use in humid conditions;
OSB/4 heavy duty load-bearing boards for use in humid conditions.
NOTE Load-bearing boards are intended for use in the design and construction of load-bearing or stiffening building elements e.g. walls, flooring, roofing and I-beams (see EN 1995-1-1 and/or performance standards) for use in dry or humid conditions
5 General requirements for all OSB types
Oriented Strand Boards shall comply with the general requirements listed in Table 1 when dispatched from the producing factory.
NOTE On delivery of OSB panels, their moisture content should be determined prior to use, and allowed to come into equilibrium with the ambient climatic conditions.BS 300 pdf download.