National foreword

This British Standard is the UK implementation of EN 336:2013. It supersedes BS EN 336:2003, which is withdrawn.

The UK participation in its preparation was entrusted to Technical Committee B/518, Structural timber.

A list of organizations represented on this committee can be obtained on request to its committee manager.

The UK committee draws users’ attention to National Annex NA, which provides further guidance to assist users in the application of this standard.

Contractual and legal considerations

This publication has been prepared in good faith, however no representation, warranty, assurance or undertaking (express or implied) is or will be made, and no responsibility or liability is or will be accepted by BSI in relation to the adequacy, accuracy, completeness or reasonableness of this publication. All and any such responsibility and liability is expressly disclaimed to the full extent permitted by the law.

This publication is provided as is, and is to be used at the recipient’s own risk.

The recipient is advised to consider seeking professional guidance with respect to its use of this publication.

This publication is not intended to constitute a contract. Users are responsible for its correct application.

Compliance with a British Standard cannot confer immunity from legal obligations.

This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 October 2013.

This European Standard was approved by CEN on 24 August 2013.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Slovenia, Sweden, Switzerland, Turkey and United Kingdom.

Foreword

This document (EN 336:2013) has been prepared by Technical Committee CEN/TC 124 “Timber structures”, the secretariat of which is held by AFNOR.

This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by April 2014, and conflicting national standards shall be withdrawn at the latest by April 2014.

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.

This document will supersede EN 336:2003.

Compared to EN 336:2003, the following modifications have been made:

in the scope, the limit to 300 mm is deleted so the standard is available for large cross section;
minimum size changed from 22 mm to 6 mm;
in subclause 4.2, the changes in size due to changes in moisture content are given for hardwoods;
in subclause 4.3, the permitted cross sectional deviations are given for thicknesses and widths above 300 mm;
in Clause 5, moisture content measurement in accordance with the three parts of EN 13183.

According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.

Introduction

Target size is the basis for the standard.

A method of calculating sizes at other moisture levels is provided.

The standard also stipulates a method for the measurement of moisture content.

1 Scope

This European Standard specifies two classes of permitted deviations from target sizes for structural timber of softwood and hardwood species.

It also specifies the moisture content to be used as a reference point for the measurement of sizes, and gives average values for changes in size due to changes in moisture content.

It is applicable to sawn and prepared square-edged structural timber with parallel edges having sawn thicknesses or widths greater than 6 mm.

2 Normative references

3 Terms and definitions

4 Sizes for structural timber

4.1 General

4.2 Changes in size due to changes in moisture content

4.3 Permitted cross-sectional deviations

4.4 Permitted length deviations

5 Moisture content measurement

Bibliography

BS EN 336:2013

Structural timber. Sizes, permitted deviations

Current, Under Review

Published:

30 Jun 2021