1、BSI Standards PublicationPD CEN/TR 16816:2015End use performance of woodproducts Utilisation andimprovement of existingmethods to estimate servicelifePD CEN/TR 16816:2015 PUBLISHED DOCUMENTNational forewordThis Published Document is the UK implementation of CEN/TR16816:2015.The UK participation in i
2、ts preparation was entrusted to TechnicalCommittee B/515, Wood preservation.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. Users are responsible for its correctap
3、plication. The British Standards Institution 2015. Published by BSI StandardsLimited 2015ISBN 978 0 580 88431 3ICS 79.080Compliance with a British Standard cannot confer immunity fromlegal obligations.This Published Document was published under the authority of theStandards Policy and Strategy Commi
4、ttee on 30 April 2015.Amendments issued since publicationDate Text affectedPD CEN/TR 16816:2015TECHNICAL REPORT RAPPORT TECHNIQUE TECHNISCHER BERICHT CEN/TR 16816 April 2015 ICS 79.080 English Version End use performance of wood products - Utilisation and improvement of existing methods to estimate
5、service life Performances des produits en bois dans leur emploi - Utilisation et amlioration des mthodes existantes pour estimer la dure de vie Leistungseigenschaften von Holzprodukten This Technical Report was approved by CEN on 21 March 2015. It has been drawn up by the Technical Committee CEN/TC
6、38. 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, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Po
7、land, 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 Management Centre: Avenue Marnix 17, B-1000 Brussels 2015 CEN All rights of exploitatio
8、n in any form and by any means reserved worldwide for CEN national Members. Ref. No. CEN/TR 16816:2015 EPD CEN/TR 16816:2015CEN/TR 16816:2015 (E) 2 Contents Page Foreword 3 1 Scope 4 2 Background 4 2.1 General 4 2.2 ISO/TC 59/SC14 “Design life” .4 2.3 CEN/TC 350 Sustainability of Construction Words
9、5 2.4 CEN/TC 351 Construction Products: Assessment of release of dangerous substances 5 2.5 COST Action E37 sustainability through new technologies for enhanced wood durability 5 2.6 WoodExter project .6 2.7 Design value IRdfor resistance factor depending on material 6 3 Work in this area continued
10、in the Swedish led project WoodBuild 2008-2013.CEN/TC38 Standards: requirements for efficacy 8 3.1 Preservative treated wood 8 3.2 Naturally durable wood .9 4 Guidance on the determination of end use performance of wood products . 10 5 Guidance on utilization and improvement of existing methods to e
11、stimate service life 11 5.1 General . 11 5.2 Gap analysis of existing standards in TC38 to inform on service life 11 6 Actions . 30 6.1 General . 30 6.2 WG21 30 6.3 WG23 31 6.4 WG25 31 6.5 WG24 31 7 Acknowledgements 32 Bibliography . 33 PD CEN/TR 16816:2015CEN/TR 16816:2015 (E) 3 Foreword This docum
12、ent (CEN/TR 16816:2015) has been prepared by Technical Committee CEN/TC 38 “Durability of wood and wood-based products”, the secretariat of which is held by AFNOR. 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
13、 shall not be held responsible for identifying any or all such patent rights. PD CEN/TR 16816:2015CEN/TR 16816:2015 (E) 4 1 Scope The scope of WG28 Performance Classification is expressed in this Technical Report: Guidance on the determination of end use performance of wood products: utilization and
14、 improvement of existing test methods to estimate service life, in order to give input to the harmonized product standards dealing with the durability requirement of the CPD and future Regulation (EU) No 305/2011 (The Construction Products Regulation CPR). This Technical Report brings together the e
15、valuations and discussions to date that have occurred within CEN/TC38/WG28 Performance Classification. This technical report does not address panel products specifically. 2 Background 2.1 General The development of performance-based design methods for durability requires that models are available to
16、 predict performance in a quantitative and probabilistic format. The relationship between performance during testing and in service needs to be quantified in statistical terms and the resulting predictive models need to be calibrated to provide a realistic measure of service life, including a define
17、d acceptable risk of non-conformity. Service-life prediction or planning is a process for ensuring that, as far as possible, the service life of a building will equal or exceed its design life, while taking into account (and preferably optimising) its life-cycle costs (ISO 15686 1). For a long time,
18、 the international organizations CIB and RILEM have been leading this development, which has had an impact on standardization work nationally, regionally, and globally through ISO. Service-life prediction should be integrated into the design process for constructions, but it is also applicable to ex
19、isting buildings and other construction works. Drivers for establishing service-life planning methodology and routines include the need for building owners to be able to forecast and control costs throughout the design life of a building or construction. It also influences the reliability of constru
20、cted assets, and hence the health and safety of users. The construction sector is under pressure to improve its cost effectiveness, quality, energy efficiency and environmental performance and to reduce the use of non-renewable resources. A key issue for the competitiveness of wood is the delivery o
21、f reliable components of controlled durability with minimum maintenance needs and life-cycle costs. The importance of service-life issues is reflected in the Construction Products Directive (CPD) with its six essential requirements, which should be fulfilled by construction products during a reasona
22、ble service life. 2.2 ISO/TC 59/SC14 “Design life” The development of performance-based design methods for durability requires that models are available to predict performance in a quantitative and probabilistic format. The relationship between performance during testing and in service needs to be q
23、uantified in statistical terms and the resulting predictive models need to be calibrated to provide a realistic measure of service life, including a defined acceptable risk of non-conformity. Service-life prediction or planning is a process for ensuring that, as far as possible, the service life of
24、a building will equal or exceed its design life, while taking into account (and preferably optimising) its life-cycle costs (ISO 15686 1). For a long time, the international organisations CIB and RILEM have been leading this development, which has had an impact on standardization work nationally, re
25、gionally, and globally through ISO. PD CEN/TR 16816:2015CEN/TR 16816:2015 (E) 5 Service-life prediction should be integrated into the design process for constructions, but it is also applicable to existing buildings and other construction works. Drivers for establishing service-life planning methodo
26、logy and routines include the need for building owners to be able to forecast and control costs throughout the design life of a building or construction. It also influences the reliability of constructed assets, and hence the health and safety of users. The construction sector is under pressure to i
27、mprove its cost effectiveness, quality, energy efficiency and environmental performance and to reduce the use of non-renewable resources. A key issue for the competitiveness of wood is the delivery of reliable components of controlled durability with minimum maintenance needs and life-cycle costs. T
28、he importance of service-life issues is reflected in the Construction Products Directive (CPD) with its six essential requirements, which should be fulfilled by construction products during a reasonable service life. 2.3 CEN/TC 350 Sustainability of Construction Words CEN/TC 350 is responsible for t
29、he development of voluntary horizontal standardized methods for the assessment of the sustainability aspects of new and existing construction works and for standards for the environmental product declaration of construction products. The objective is to ensure that LCA-based data for environmental p
30、roduct declarations are consistent, comparable, verifiable and scientifically based. Since the life cycle has to be defined, it is essential to include information on service lives, including reference service lives. Methods for sustainability assessments should be based on a performance-based appro
31、ach, and should cover environmental, social and economic performance. 2.4 CEN/TC 351 Construction Products: Assessment of release of dangerous substances The work of CEN/TC 351 is directed to the area covered by the Biocidal Products Directive and REACH. Indicators, criteria and developed standards
32、will have significant influence in the future on the materials available for construction products and on service-life design options. 2.5 COST Action E37 sustainability through new technologies for enhanced wood durability The Task Force Performance Classification (TFPC) was established at the COST
33、 Action E37 workshop in Ljubljana in 2004 2. Its aim was to outline principles for a performance-based classification of wood durability, in particular in using the natural durability of untreated wood and for modified wood products, traditional and non-traditional treatments and non-biocidal measur
34、es for wood protection. The COST Action ended in September 2008, and the TFPC submitted a final report for inclusion in the overall documentation of the Action 3. Standards for durability of wood and wood-based products, not least those produced by CEN/TC 38 Durability of wood and wood-based materia
35、ls, were of primary interest to the TFPC. They considered that the present standards could not deliver adequate performance-based data. One goal of the Task Force was therefore to address the way durability is treated in standardization. It was conceived that well-founded proposals on amalgamating m
36、odern, material-independent methods of service-life prediction and design with traditional wood assessment methods would be of direct use, e.g. to CEN/TC 38 and the construction industry. The TFPC recognized the use of Reference Service Life (RSL) as a basis for estimations of Estimated Service Life
37、 (ESL). The estimates are not necessarily reached by use of the Factor Method as in ISO 15686, but the basic principle is useful. To develop a range of performance classes, the scientific community must connect better and cooperate with user groups and stakeholders and define reference products that
38、 can be evaluated under reference service conditions. Test results on any commodities, products and components will then be compared with agreed RSLs, and this can form the foundation for a range of performance classes. During this development, existing use classes have to be taken into account and,
39、 if necessary, adapted to suit a PD CEN/TR 16816:2015CEN/TR 16816:2015 (E) 6 forthcoming system for performance classification. As an input to Factor A (Quality of components) in the Factor Method, it will be necessary to define a range of Resistance Classes to feed into the assessments. This work i
40、s carried forward in CEN/TC 38 WG28 and the WoodExter project. 2.6 WoodExter project The WoodExter project 4 (2007 2010) was a collaborative pan-European-funded research project supported by WoodWisdom-Net and the Building with Wood industry initiative. Its objective was to take the first steps towa
41、rds introducing performance-based engineering design for wood and wood-based building components in outdoor above-ground situations. This enables capture of the benefits of design for durability and has delivered a practical engineering tool for service-life estimation based on a novel methodology.
42、The project focused on cladding and decking as two test case products to rigorously assess this methodology. The project aims were to: characterize climatic influence on performance of timber cladding; characterize new and existing techniques as in-service indicators of performance prediction; combi
43、ne the above in an engineering-based model; calibrate and rigorously test the model for the selected Use Class 3 products, cladding and decking; transfer knowledge to enable confident specification of timber cladding and decking. A pilot model has been developed in the WoodExter project incorporatin
44、g key input data and the interactions between them that influence performance of cladding www.kstr.lth.se/guideline. The consequence class depends on the severity of consequences in case of non-performance and is described by the factor d. The exposure index Iskis conceived as a characteristic (safe
45、) value accounting for uncertainties. The exposure index is assumed to depend on: geographical location determining global climate; local climate conditions; the degree of sheltering; distance from the ground; detailed design of the wood component; use and maintenance of coatings. 2.7 Design value I
46、Rdfor resistance factor depending on material The design resistance index IRdfor selected wood materials is determined on the basis of resistance class according to Table 1. This is a simplified first step for a material resistance classification based on a balanced expert judgment of moisture dynam
47、ics and durability class. The resistance class term is based on a combination of durability class data according to EN 350-2, test data, experience of treatability and permeability for wood species as well as experience from practice. Biological durability is the key factor determining performance f
48、or wood in different use classes. The robust laboratory and field test methods that exist make it possible to assign a durability rating to timber linked to the intended use class according to EN 335, assuming a worst case scenario. Other factors determine the likelihood of the worst case scenario o
49、ccurring in practice. PD CEN/TR 16816:2015CEN/TR 16816:2015 (E) 7 The natural durability of wood is classified into durability classes as described in EN 350-1 and presented as durability classes for heartwood of timber species in EN 350-2. Durability class is a classification on five levels from non-durable to very durable. This is based on decades of data from ground contact field trials for use class 4. The natural durability for a wood species can vary widely. Table 1 Resistance classification of selected wood materials and corresp
