BS EN 942-2007 Timber in joinery - General requirements《细木工业用木材 一般要求》.pdf

1、BRITISH STANDARD BS EN 942:2007 Timber in joinery General requirements The European Standard EN 942:2007 has the status of a British Standard ICS 79.040 BS EN 942:2007 This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 April 2007 BSI 2007 ISB

2、N 978 0 580 50496 9 National foreword This British Standard was published by BSI. It is the UK implementation of EN 942:2007. It supersedes BS EN 942:1996 which is withdrawn. The UK participation in its preparation was entrusted to Technical Committee B/543, Round and sawn timber. A list of organiza

3、tions represented on B/543 can be obtained on request to its secretary. National Annex NA contains tables that give information on some species and their suitability for use in joinery. These tables are reproduced from BS 1186-1:1991 which was withdrawn on publication of the 1996 edition of BS EN 94

4、2. They were included in the National Annex NA to BS EN 942:1996 and are reproduced here again in this edition for information. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standa

5、rd cannot confer immunity from legal obligations. Amendments issued since publication Amd. No. Date CommentsEUROPEANSTANDARD NORMEEUROPENNE EUROPISCHENORM EN942 March2007 ICS79.040 SupersedesEN942:1996 EnglishVersion TimberinjoineryGeneralrequirements BoisdanslesmenuiseriesExigencesgnrales HolzinTis

6、chlerarbeitenAllgemeineAnforderungen ThisEuropeanStandardwasapprovedbyCENon11January2007. CENmembersareboundtocomplywiththeCEN/CENELECInternalRegulationswhichstipulatetheconditionsforgivingthisEurope an Standardthestatusofanationalstandardwithoutanyalteration.Uptodatelistsandbibliographicalreference

7、sconcernings uchnational standardsmaybeobtainedonapplicationtotheCENManagementCentreortoanyCENmember. ThisEuropeanStandardexistsinthreeofficialversions(English,French,German).Aversioninanyotherlanguagemadebytra nslation undertheresponsibilityofaCENmemberintoitsownlanguageandnotifiedtotheCENManagemen

8、tCentrehasthesamestatusas the officialversions. CENmembersarethenationalstandardsbodiesofAustria,Belgium,Bulgaria,Cyprus,CzechRepublic,Denmark,Estonia,Finland, France,Germany,Greece,Hungary,Iceland,Ireland,Italy,Latvia,Lithuania,Luxembourg,Malta,Netherlands,Norway,Poland,P ortugal, Romania,Slovakia,

9、Slovenia,Spain,Sweden,SwitzerlandandUnitedKingdom. EUROPEANCOMMITTEEFORSTANDARDIZATION COMITEUROPENDENORMALISATION EUROPISCHESKOMITEEFRNORMUNG ManagementCentre:ruedeStassart,36B1050Brussels 2007CEN Allrightsofexploitationinanyformandbyanymeansreserved worldwideforCENnationalMembers. Ref.No.EN942:200

10、7:EEN 942:2007 (E) 2 Contents Page Foreword3 Introduction .4 1 Scope5 2 Normative references5 3 Terms and definitions .5 4 Basic principles.6 4.1 Appearance classes6 4.2 Species.6 4.3 Density6 4.4 Growth rings.6 4.5 Surface quality.6 4.6 Moisture content7 4.7 Finger-jointing, butt-jointing, edge-joi

11、nting and laminating .7 5 Classification of features 7 5.1 General7 5.2 Knots and knot clusters8 5.2.1 Types.8 5.2.2 Size8 5.2.3 Distribution.8 6 Remedial work9 6.1 Plugs and fillers .9 6.2 Requirements.9 Annex A (normative) Measurement of dimensions of finished pieces13 Annex B (informative) Guide

12、to moisture content in joinery 15 Annex C (informative) Guide to specifying timber in joinery16 C.1 information to be supplied16 C.2 Identifying characteristics, techniques or remedies and their acceptability with visible surfaces 16 Annex D (informative) The selection of timber species for use in j

13、oinery 18 D.1 General18 D.2 Aesthetic criteria18 D.3 Commercial criteria.18 D.4 Mechanical criteria.18 D.5 Durability criteria.19 D.6 Serviceability criteria.19 D.7 Workability criteria.19 Bibliography 23 National annex NA (informative) Some species and their suitability for use in joinery25EN 942:2

14、007 (E) 3 Foreword This document (EN 942:2007) has been prepared by Technical Committee CEN/TC 175 “Round and sawn timber”, 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

15、, at the latest by September 2007, and conflicting national standards shall be withdrawn at the latest by October 2007. This document supersedes EN 942:1996. This Standard is one of a package to be implemented on 2007.10.31. The Standards included in the Package are: Standard Number Title 1 EN 942 R

16、evised Timber in joinery - General requirements 2 EN 13307-1 Timber blanks and semi-finished profiles for non- structural uses Part 1: Requirements 3 EN 14220 Timber and wood-based materials in external windows, external door leaves and external doorframes Requirements and specifications 4 EN 14221

17、Timber and wood-based materials in internal windows, internal door leaves and internal doorframes - Requirements and specifications Explanation Standards 3 and 4 rely on both Standards 1 and 2, and Standard 2 relies on 1. The revised EN 942 contains changes which directly affect standards 2, 3 and 4

18、 and therefore must be available before they can be used effectively. NOTE Following the completion of the Technical Enquiry for prEN 13307-2, Timber blanks and semi-finished profiles for non-structural uses Part 2: Production control, it has been agreed to remove this Standard from the package. As

19、a result of the necessary changes it has been agreed to offer prEN 13307-2 as a CEN/TS. 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, Cyprus, Czech Republic

20、, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EN 942:2007 (E) 4 Introduction Commercial grades, i.e. the

21、grade given to timber as a raw material, are not appropriate for referencing in joinery specifications. This European Standard specifies the general grading requirements to be used to determine the characteristics and classify, by appearance, the quality of timber in joinery. This method is not appr

22、opriate for the purchase specification of timber. This standard provides only recommendations for the moisture content of timber. Specific moisture contents are covered in the specific product standards. EN 942:2007 (E) 5 1 Scope This European Standard specifies the general requirements including in

23、 particular the grading and classification by appearance quality of timber in joinery products or individual joinery parts. This European Standard is intended to be used at the time of manufacture of a product. However this Standard may be used to evaluate products at a later stage, but in these sit

24、uations storage and service conditions, subsequent to manufacture, shall be taken into account (surface checks). Where European product standards exist their timber requirements shall take precedence, unless an alternative improved specification is given as identified in Annex D. If reference to thi

25、s European Standard is made the specific grade and requirements shall be identified. This European Standard covers solid, finger-jointed, end-jointed, edge-jointed and laminated timber products. Matters relating to the influence of timber characteristics on strength and durability are not covered in

26、 this Standard. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 350-2,

27、Durability of wood and wood-based products Natural durability of solid wood - Part 2: Guide to natural durability and treatability of selected wood species of importance in Europe. EN 844-3:1995, Round and sawn timber - Terminology - Part 3: General terms related to sawn timber EN 1310, Round and sa

28、wn timber - Method of measurement of features EN 13183-1, Moisture content of a piece of sawn timber Part 1: Determination by oven dry method EN 13183-2, Moisture content of a piece of sawn timber Part 2: Estimation by electrical resistance method EN 13183-3, Moisture content of a piece of sawn timb

29、er Part 3: Estimation by capacitance method 3 Terms and definitions For the purposes of this document, the terms and definitions given in EN 844-3:1995 and the following apply. 3.1 joinery wood and wood-based products graded for non-structural use within a building NOTE These grading rules do not ap

30、ply to wood-based panels covered by EN 13986. 3.2 concealed face face of a joinery part which, after installation of the joinery is completed, is permanently concealed by other parts of the joinery product, by other parts or by other elements including sheet materials such as veneer, solid plastic o

31、r metal NOTE These faces may be visible before the product is installed. EN 942:2007 (E) 6 3.3 semi-concealed face visible face of a joinery part which cannot be viewed when the product is in the closed position 3.4 visible face face of a joinery part which, after installation of the joinery is comp

32、leted, is not permanently concealed or semi- concealed NOTE 1 An opaque paint finish, does not constitute concealment. NOTE 2 Faces which are visible when moving parts (e.g. shutters) are open are classified as semi-concealed. 4 Basic principles 4.1 Appearance classes Timber in joinery shall be clas

33、sified by referencing a number of basic features which are given in Clause 5 and summarised in Table 1. In addition, a number of other factors shall be taken into account and these are given in the rest of Clause 4. Any feature is accepted on a concealed face if the serviceability of the product is

34、not impaired. 4.2 Species Timber in joinery shall be suitable for its intended purpose. NOTE 1 Guidance on the specification of timber in joinery is given in Annex C and on the selection of timber species in Annex D. NOTE 2 Durability, a factor influencing the performance of timber, is covered by EN

35、 335-2, EN 350-2, EN 460 and EN 351-1. NOTE 3 It should be noted that colour variations occur within species as well as between sapwood and heartwood. Any special requirements for colour matching should be by prior agreement. NOTE 4 If two or more species are used in the same unit or sub-assembly, t

36、hey should be selected to avoid differential movement resulting in distortion. 4.3 Density The density of timber used will have a significant effect on mechanical performances. Reference densities for common species are given in EN 350-2. 4.4 Growth rings Limits on growth rings are not specified wit

37、hin the grading rules. If the number and width of growth rings are to be specified, the measurement method shall be the method given in EN 1310. NOTE Where the width and number of growth rings may affect the mechanical performance of a product or the fabrication of glued components (laminated profil

38、es), reference should be made to the appropriate product standard. 4.5 Surface quality The surface of timber in visible faces shall be able to accept a coating system without any further operation other than light sanding. EN 942:2007 (E) 7 4.6 Moisture content The measurement of the moisture conten

39、t of the timber in a product is applicable at the completion time of the product manufacture and prior to the application of any coating. The moisture content (percent) of the timber shall be in accordance with the relevant product standard or national requirements. NOTE 1 Where a relevant product s

40、tandard or national requirement does not exist, the guidance on moisture content given in Annex B is recommended. The moisture content shall be estimated using, either the method described in EN 13183-2, or EN 13183-3. In the case of a dispute the method to be used shall be the method described in E

41、N 13183-1 (Destructive method). NOTE 2 The more accurate method described in EN 13183-1 is a destructive method and may not always be appropriate. 4.7 Finger-jointing, butt-jointing, edge-jointing and laminating Unless otherwise agreed, finger-jointing, butt-jointing and edge-jointing shall be permi

42、tted in classes J10, J20, J30, J40 and J50 according to Table 1 but shall not be permitted in class J2 and J5, unless accepted by a product standard. The distance between the centres of finger-joints and butt-joints shall be at least 150 mm. Laminating sections in any class shall be permitted unless

43、 otherwise agreed. 5 Classification of features 5.1 General The appearance classes in Table 1 are independent of the species. The limits set in Table 1 for each feature relative to the specific class shall not be exceeded when a specific class is specified. The classification of features can be miss

44、ed subject to the declaration of the class for each feature as given in Table D.1 (See example in Table D.2). Table 1 shows where and to what extent the presence of the following features shall be permitted at the time of handover, for the various classes of timber. NOTE 1 Handover relates to the ti

45、me the joinery is supplied by the manufacturer to the first purchaser. NOTE 2 The classes in Table 1 generally apply to visible faces. Unless otherwise specified semi-concealed faces, in the same product, may be graded up to two classes lower and concealed faces may be any lower class. The following

46、 features are identified in Table 1: - spiral grain; - slope of grain; - loose or unsound knots; - knots; - resin pockets; - bark pockets; - fissures, shakes; EN 942:2007 (E) 8 - exposed pith; - discoloured sapwood; - ambrosia beetle damage. Where remedial work on the part of the manufacturer is per

47、mitted in Table 1, it shall be carried out in accordance with clause 6. The measurement of features shall be carried out in accordance with the general method given in EN 1310. NOTE See also the guidance given in C.2. The following features are generally not permitted : - reaction wood; - splits; -

48、biological attack; - wane. 5.2 Knots and knot clusters 5.2.1 Types Knots and knot clusters shall be limited in size and distribution, according to 5.2.2 and 5.2.3. Loose or unsound knots shall not be present except on concealed faces. When they occur on a visible face, the timber shall be repaired in accordance with clause 6. Arris knots shall comply with the requirements of both faces on which they appear. NOTE Arris knots may be impossible to repair unless extremely sound. 5.2.2 Size Unless otherwise specified in the relevant product standa