1、BSI Standards PublicationPD CEN/TR 12872:2014Wood-based panels Guidance on the use of load-bearing boards in floors, wallsand roofsPD CEN/TR 12872:2014 PUBLISHED DOCUMENTNational forewordThis Published Document is the UK implementation of CEN/TR 12872:2014. It supersedes DD CEN/TS 12872:2007 which i
2、swithdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee B/541, Wood based panels.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Use
3、rs are responsible for its correctapplication. The British Standards Institution 2014. Published by BSI StandardsLimited 2014ISBN 978 0 580 87278 5ICS 79.060.01Compliance with a British Standard cannot confer immunity fromlegal obligations.This Published Document was published under the authority of
4、 theStandards Policy and Strategy Committee on 31 December 2014.Amendments issued since publicationDate Text affectedPD CEN/TR 12872:2014TECHNICAL REPORT RAPPORT TECHNIQUE TECHNISCHER BERICHT CEN/TR 12872 December 2014 ICS 79.060.01 Supersedes CEN/TS 12872:2007English Version Wood-based panels - Gui
5、dance on the use of load-bearing boards in floors, walls and roofs Panneaux base de bois - Guide pour lutilisation des panneaux structurels en planchers, murs et toitures Holzwerkstoffe - Leitfaden fr die Verwendung von tragenden Platten in Bden, Wnden und Dchern This Technical Report was approved b
6、y CEN on 11 November 2014. It has been drawn up by the Technical Committee CEN/TC 112. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Ice
7、land, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Mana
8、gement Centre: Avenue Marnix 17, B-1000 Brussels 2014 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. CEN/TR 12872:2014 EPD CEN/TR 12872:2014CEN/TR 12872:2014 (E) 2 Contents Page Foreword 4 1 Scope 5 2 Normative references 5 3 Terms a
9、nd definitions .5 4 Information on product performance 7 5 Inspection at site7 6 Transport and delivery 7 7 Handling 7 8 Stacking 7 9 Storage 9 10 Moisture content, conditioning and the effects of moisture .9 10.1 Moisture content 9 10.2 Dimensional movement 9 10.3 Conditioning 10 11 Cutting and mac
10、hining . 11 11.1 General . 11 11.2 Cutting with hand tools 11 11.3 Machining with power tools . 11 11.4 Drilling 12 12 Fixing . 12 13 Floors Selection and installation 13 13.1 Selection (specification) 13 13.2 Type of floor covering related to wood-based floor panels . 13 13.3 Installation . 14 13.3
11、.1 Preparation of structure . 14 13.3.2 Edge profile . 14 13.3.3 Expansion gaps 14 13.3.4 Gluing . 15 13.3.5 Laying of wood-based panels for flooring . 15 14 Walls Selection and installation . 16 14.1 Selection (specification) 16 14.2 Wall constructions using wood-based panels on studs 16 14.3 Insta
12、llation . 16 14.3.1 Preparation of structure . 16 14.3.2 Edge profile . 17 14.3.3 Expansion gaps 17 14.3.4 Assembly of wood-based panels for walls on studs 18 15 Roofs Selection and installation. 19 15.1 Selection (specification) 19 15.2 Type of roof covering related to wood-based roof panels . 19 1
13、5.3 Type of roofs . 19 15.3.1 Flat roofs: cold roofs warm roofs . 19 15.3.2 Pitched roofs principles 20 15.4 Installation . 21 PD CEN/TR 12872:2014CEN/TR 12872:2014 (E) 3 15.4.1 Preparation of structure 21 15.4.2 Edge profile 21 15.4.3 Expansion gaps . 22 15.4.4 Laying of wood-based panels in roof s
14、tructures . 22 Bibliography 24 PD CEN/TR 12872:2014CEN/TR 12872:2014 (E) 4 Foreword This document (CEN/TR 12872:2014) has been prepared by Technical Committee CEN/TC 112 “Wood-based panels”, the secretariat of which is held by DIN. Attention is drawn to the possibility that some of the elements of t
15、his 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 supersedes CEN/TS 12872:2007. Compared to CEN/TS 12872:2007 the following changes have been made: a) deliverability changed from CEN/TS to C
16、EN/TR; b) references to requirements according to EN 12871 deleted after transformation of EN 12871 into a test method standard; c) in 10.2, Table 2, values of dimensional changes depending on moisture content for multilayer solid wood panels added; d) presentation of wall and roof constructions in
17、Clauses 14 and 15 indicated as basic examples; e) recommended expansion gaps for walls and roofs in Clauses 14 and 15 reduced. PD CEN/TR 12872:2014CEN/TR 12872:2014 (E) 5 1 Scope This Technical Report gives guidance on the use of wood-based panels in structural applications as structural floor and r
18、oof decking on joists or structural wall sheathing on studs in accordance with EN 12871. It provides information on: inspection at site; transport and delivery; handling; stacking; storage; moisture content, conditioning and the effects of moisture; cutting and machining; selection; installation. 2
19、Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendme
20、nts) applies. EN 300, Oriented Strand Boards (OSB) - Definitions, classification and specifications EN 312, Particleboards - Specifications EN 622-2, Fibreboards - Specifications - Part 2: Requirements for hardboards EN 622-3, Fibreboards - Specifications - Part 3: Requirements for medium boards EN
21、622-5, Fibreboards - Specifications - Part 5: Requirements for dry process boards (MDF) EN 634-2, Cement-bonded particleboards - Specifications - Part 2: Requirements for OPC bonded particleboards for use in dry, humid and external conditions EN 636, Plywood - Specifications EN 12871, Wood-based pan
22、els - Determination of performance characteristics for load bearing panels for use in floors, roofs and walls EN 13353, Solid wood panels (SWP) - Requirements EN 1995-1-1:2004, Eurocode 5 Design of timber structures Part 1-1: General Common rules and rules for buildings 3 Terms and definitions For t
23、he purposes of this document, the following terms and definitions apply. PD CEN/TR 12872:2014CEN/TR 12872:2014 (E) 6 3.1 Service classes 3.1.1 service class 1 is characterised by a moisture content in the materials corresponding to a temperature of 20 C and the relative humidity of the surrounding a
24、ir only exceeding 65 % for a few weeks per year EN 1995-1-1:2004, 2.3.1.3 3.1.2 service class 2 is characterised by a moisture content in the materials corresponding to a temperature of 20 C and the relative humidity of the surrounding air only exceeding 85 % for a few weeks per year EN 1995-1-1:200
25、4, 2.3.1.3 3.1.3 service class 3 climatic conditions leading to higher moisture contents than in service class 2 EN 1995-1-1:2004, 2.3.1.3 3.2 structural floor decking assembly of wood-based panels supported on joists over which the decking spans Note 1 to entry: The characteristic of the floor deck
26、ing is that it is supported by joists and, when subjected to load, is free to deflect between the joists. 3.3 structural wall sheathing wood-based panel capable of providing mechanical resistance to a wall structure 3.4 structural roof decking assembly of wood-based panels supported on joists over w
27、hich the roof decking spans Note 1 to entry: The characteristic of the decking is that it is supported by joists and, when subjected to load, is free to deflect between the joists. 3.5 warm roof roof design in which the panels supported on joists are placed below the insulation Note 1 to entry: The
28、panels are considered to be under conditions corresponding to service class 1. 3.6 cold roof roof design in which the panels and some of the supporting joists are placed above the insulation Note 1 to entry: The panels are considered to be under conditions corresponding to service class 2. 3.7 sub f
29、loor structural panel meant to be covered by overlays PD CEN/TR 12872:2014CEN/TR 12872:2014 (E) 7 4 Information on product performance Information on product performance based on EN 13986 will be made available by the manufacturer or supplier. 5 Inspection at site The following should be checked bas
30、ed on the marking of the panel and/or the manufacturers documentation and/or the designers specification: grade or class according to EN specification standard; thickness; service class; suitability for biological durability use class; surface (sanded or un-sanded); edges (tongue and groove or other
31、 type of profile); joist or stud spacing; load category; main load-bearing direction for OSB, plywood and solid wood panels only. 6 Transport and delivery Panels should be adequately protected by a waterproof covering during transportation. Edges should be well protected from rain or traffic spray.
32、Edge protection should also be provided to avoid damage by ropes, straps or other banding. This applies particularly to profiled panels such as tongued and grooved panels. Panels should be stacked properly to avoid sagging or other distortion, see Clause 8. If packing includes banding or strapping t
33、his should be removed as soon as possible after delivery to prevent any permanent deformation of the panels. When packs are delivered with edge or face protection panels, these should be left in place until the pack is required for use. 7 Handling When lifting, moving and stacking panels, edge prote
34、ction should also be provided to avoid damage by lifting ropes and/or forklifts. When handling pre-finished panels, it is essential to avoid damage or dirt on the finished surfaces. Pre-finished panels should always be lifted from a stack and never slid. 8 Stacking Panels should be stacked flat on a
35、 level surface with all four edges flush. The ideal base is a close boarded or slatted pallet. If this is not possible the panels should be carefully stacked on battens of equal thickness at centres not exceeding 600 mm as shown in Figure 1. PD CEN/TR 12872:2014CEN/TR 12872:2014 (E) 8 Intermediate b
36、attens are recommended every 15 to 20 panels to allow through ventilation, they shall be placed directly above those below. The battens should be placed parallel to the short edges across the full width. Overhang of the panels at the ends of the stack should not exceed 150 mm. Where stacks are place
37、d on top of one another, the bearers should line up vertically to prevent distortion. The top of the stack should be covered. Stacking on edge should be avoided whenever possible. Where space will only permit edge stacking then the edges should not be permitted to come into direct contact with the f
38、loor to avoid possible moisture pick-up or damage to the edges. Panels should not be leant against walls but supported by a braced, purpose made rack using thick ( 18 mm) base and back panels (see Figure 2). In case of tongued and grooved panels, edge stacking on the tongue should be avoided. Dimens
39、ions in millimetres CORRECT INCORRECT Figure 1 Panel storage Figure 2 Correct method of edge stacking PD CEN/TR 12872:2014CEN/TR 12872:2014 (E) 9 9 Storage Wood based panels can be susceptible to damage from high levels of moisture and measures should be taken to prevent such elevated levels of mois
40、ture during transport and subsequent storage, in particular protect from rain or standing water. Panels should preferably be stored in an enclosed dry building. Where temporary storage outside cannot be avoided, then stacks should be covered with waterproof but vapour permeable sheeting, keeping all
41、 panels on raised bearers to prevent contact with the ground, water or vegetation. Any protective wrapping should be kept in place as long as possible prior to conditioning for use. 10 Moisture content, conditioning and the effects of moisture 10.1 Moisture content Moisture content of wood-based pan
42、el products varies in accordance with the moisture condition of the surrounding environment, and is affected primarily by the relative humidity (rh) of the surrounding air. It moves towards and maintains an equilibrium moisture content (emc) i.e. one that is in equilibrium with the surrounding air.
43、This means that moisture contents in wood-based panel products will vary depending on the situation of use and with time as temperature and humidity conditions change. Although it is not possible to give precise levels, the figures in Table 1 give a general indication of the range of moisture conten
44、ts in wood-based panels in various conditions. Table 1 Equilibrium moisture content and conditions of use Service class Normal range of relative humidity (rh) at 20 C Approximate equilibrium moisture content (emc) Conditions of use 1 30 % to 65 % 4 % emc 11 % Dry installations, no risk of wetting in
45、 service 2 65 % to 85 % 11 % emc 17 % Risk of wetting during installation and risk of occasional wetting in service 3 85 % emc 17 % Risk of regular wetting in service The moisture content of panels when they leave the factory can be as low as 2 % depending on the type of panel. NOTE The allowable mo
46、isture content range is stated in the respective product standard. This indicates that unconditioned newly manufactured panels can increase in moisture content when installed in a building under construction and subsequently change in moisture content as the building is occupied, heated and dries ou
47、t, with the consequence of dimensional changes, see ranges given in 10.2. 10.2 Dimensional movement Timber and wood-based panels expand on taking up moisture from the surrounding air, and shrink on losing moisture. Excessive changes in moisture content may therefore lead to unacceptable dimensional
48、changes which may result in bowing, buckling or open joints between panels. Panels should be protected from rain, dampness and accidental wetting and prior to fixing be conditioned to the moisture content corresponding to the moisture conditions of end use. PD CEN/TR 12872:2014CEN/TR 12872:2014 (E)
49、10 Problems which may occur if insufficient care is taken with protection or conditioning include edge swelling due to moisture ingress at unprotected edges, localised swelling due to moisture pick-up from adjacent materials which have a higher moisture content, e.g. timber joists, and general expansion causing bowing between supports or restraints. Any increase in moisture content will cause slight expansion in the panel. For guidance purposes it may be assumed that a 1 % change in panel moisture cont
