EN 15228:2009

Structural timber - Structural timber preservative treated against biological attack

This European Standard specifies general requirements for structural timber that has been treated with preservatives against biological attack.
This European Standard also specifies requirements for the evaluation of conformity and marking of preservative treated timber products when they are placed on the market.
Treatments, which include a biocide, are covered by this standard.
It does not provide details of which preservative treatments are necessary for a particular type of structural timber product to achieve a required service life, as regional climatic differences and prevalent biological agents would need to be taken into account for that purpose.
This European Standard does not cover any subsequent treatment which may be required for structural timber products which have been machined, bored or planed after the CE marking has been applied.
This standard does not cover the qualification of preservation products used to treat structural timber.

Bauholz - Bauholz für tragende Zwecke mit Schutzmittelbehandlung gegen biologischen Befall

Diese Europäische Norm legt allgemeine Anforderungen an Bauholz für tragende Zwecke, das mit Holzschutzmitteln
gegen biologischen Befall behandelt wurde, fest.
Ferner legt diese Europäische Norm Anforderungen an die Konformitätsbewertung und Kennzeichnung von
Holzprodukten fest, die mit Holzschutzmitteln gegen biologischen Befall behandelt wurden, und auf den Markt
gebracht werden sollen.
Diese Norm behandelt Schutzmittelbehandlungen.
Sie enthält keine Einzelheiten, welche Schutzmittelbehandlungen für eine besondere Art von Bauholzprodukten
zum Erzielen einer festgelegten Nutzungsdauer erforderlich sind, da dazu die unterschiedlichen
regionalen klimatischen Bedingungen und die jeweils vorherrschenden Schädlinge berücksichtigt werden
müssten.
Diese Europäische Norm behandelt nicht Nachbehandlungen, die für Bauholzprodukte erforderlich sein
können, wenn diese bearbeitet, mit Bohrungen versehen oder gehobelt wurden, nachdem die CE-Kennzeichnung
aufgebracht wurde.
Diese Norm gilt nicht für die Qualifizierung der für die Bauholzprodukte angewendeten Holzschutzmittel.

Bois de structure - Bois de structure traité avec un produit de préservation contre les attaques biologiques

La présente norme européenne spécifie les exigences générales relatives au bois de structure qui a été traité
par des produits de préservation contre les attaques biologiques.
La présente norme européenne spécifie également les exigences relatives à la conformité et au marquage
des produits en bois traités avec un produit de préservation, lorsque ceux-ci sont placés sur le marché.
Les traitements incluant un produit biocide sont couverts par la présente norme.
Elle ne donne pas de détails sur quels traitements de préservation sont nécessaires pour une type particulier
de produit de structure en bois pour atteindre une durée de vie en service prescrite, dans la mesure où les
différences climatiques régionales et les agents biologiques dominants doivent être pris en compte pour
atteindre cet objectif.
La présente norme européenne ne couvre pas les traitements complémentaires pouvant être requis pour des
produits de structure en bois ayant été usinés, mortaisés ou rabotés après application du marquage CE .
La présente norme européenne ne couvre pas la qualification des produits de traitement utilisés pour traiter le
bois de structure.

Konstrukcijski les - Konstrukcijski les, zaščiten pred biološkimi vplivi

General Information

• Status: Published
• Publication Date: 24-Mar-2009
• Withdrawal Date: 29-Sep-2009
• ICS: 71.100.50 - Wood-protecting chemicals
• ICS: 79.040 - Wood, sawlogs and sawn timber
• Technical Committee: CEN/TC 124 - Timber structures
• Drafting Committee: CEN/TC 124/WG 2 - Solid timber
• Current Stage: 9060 - Closure of 2 Year Review Enquiry - Review Enquiry
• Start Date: 02-Dec-2025
• Completion Date: 02-Dec-2025
• Directive: Harmonized Standard305/2011 - Regulation (eu) No 305/2011 of the European Parliament and of the Council of 9 march 2011 laying down harmonised conditions for the marketing of construction products and repealing council directive 89/106/eec
• Directive:

  ---

  Not Harmonized89/106/EEC - Construction products
• Mandate: M/112 - Mandate to CEN/CENELEC concerning the execution of standardization work for harmonized standards on structural timber products
• Ref Project: SIST EN 15228:2009 - Structural timber - Structural timber preservative treated against biological attack

Relations

• Refers: prEN 15497 - Finger jointed structural timber - Performance requirements and minimum production requirements
• Effective Date: 28-Jan-2026
• Refers: CEN/TR 14823:2003 - Durability of wood and wood-based products - Quantitative determination of pentachlorophenol in wood - Gas chromatographic method
• Effective Date: 28-Jan-2026
• Refers: EN 13501-1:2018 - Fire classification of construction products and building elements - Part 1: Classification using data from reaction to fire tests
• Effective Date: 28-Jan-2026
• Refers: EN 351-1:2007 - Durability of wood and wood-based products - Preservative-treated solid wood - Part 1: Classification of preservative penetration and retention
• Effective Date: 28-Jan-2026
• Refers: EN 408:2010+A1:2012 - Timber structures - Structural timber and glued laminated timber - Determination of some physical and mechanical properties
• Effective Date: 28-Jan-2026
• Refers: EN 335-1:2006 - Durability of wood and wood- based products - Definition of use classes - Part 1: General
• Effective Date: 28-Jan-2026
• Refers: EN 351-2:2007 - Durability of wood and wood-based products - Preservative-treated solid wood - Part 2: Guidance on sampling for the analysis of preservative-treated wood
• Effective Date: 28-Jan-2026
• Refers: EN 14081-1:2005 - Timber structures - Strength graded structural timber with rectangular cross section - Part 1: General requirements
• Effective Date: 28-Jan-2026
• Refers: EN 13823:2020+A1:2022 - Reaction to fire tests for building products - Building products excluding floorings exposed to the thermal attack by a single burning item
• Effective Date: 28-Jan-2026
• Refers: EN ISO 9001:2015 - Quality management systems - Requirements (ISO 9001:2015)
• Effective Date: 28-Jan-2026
• Refers: EN 384:2016+A2:2022 - Structural timber - Determination of characteristic values of mechanical properties and density
• Effective Date: 28-Jan-2026
• Refers: EN 14250:2004 - Timber structures - Product requirements for prefabricated structural members assembled with punched metal plate fasteners
• Effective Date: 28-Jan-2026
• Refers: EN 14080:2005 - Timber structures - Glued laminated timber - Requirements
• Effective Date: 28-Jan-2026
• Refers: EN 599-1:1996 - Durability of wood and wood-based products - Performance of preventive wood preservatives as determined by biological tests - Part 1: Specification according to hazard class
• Effective Date: 28-Jan-2026
• Referred By: EN 14081-1:2005+A1:2011 - Timber structures - Strength graded structural timber with rectangular cross section - Part 1: General requirements
• Effective Date: 28-Jan-2026

Overview

EN 15228:2009 is a European standard developed by the European Committee for Standardization (CEN) that establishes requirements for structural timber treated with wood preservatives to protect against biological attack. This document sets out the general requirements for the treatment of structural timber with biocidal preservatives, requirements for evaluation of conformity, and guidelines for the marking of preservative-treated timber products entering the market. However, it does not specify which preservative treatment should be used for different timber types or detailed methods for the qualification of preservation products.

EN 15228:2009 helps timber producers, specifiers, and contractors ensure that structural timber products are treated and tested for durability and biological resistance, supporting safe and sustainable construction practices.

Key Topics

• Scope and Limitations

  • Applies to structural timber treated with preservatives (including biocides) for protection against fungi, insects, and other biological agents.
  • Does not detail which preservative or level of treatment is necessary for specific types or intended service life-regional climatic factors and biological threats need to be considered locally.
  • Does not cover treatments required after machining or processing following CE marking.

• Requirements for Treated Timber

  • Timber must comply with relevant product and strength grading standards before treatment.
  • Declared classes for preservative penetration and retention, referencing standards such as EN 351-1.
  • Requirements to document and mark key aspects of treatment for traceability.

• Dangerous Substances

  • Addresses limits and declaration requirements for substances such as pentachlorophenol (PCP) and other potentially dangerous chemicals in timber.
  • Reference to conformity with European biocidal product regulations for treated timber on the market.

• Evaluation of Conformity and Factory Production Control (FPC)

  • Includes initial type testing and ongoing quality controls to ensure timber’s properties post-treatment meet standard requirements.
  • Factory production control systems must be in place, documented, and regularly updated-including traceability of preservatives, treatment processes, and compliance records.

• Marking

  • Treated timber must be clearly marked or supplied with documents specifying the treatment method, preservative type, penetration class, retention value, charge number, year of treatment, biological agents targeted, and treater identification.

Applications

EN 15228:2009 is relevant to a wide range of sectors and uses where preservative-treated structural timber is specified, including:

• Construction and Civil Engineering
  • Use in load-bearing structures such as beams, joists, rafters, and posts-especially where resistance to decay and biological attack is essential.
• Prefabricated Building Components
  • Application in manufacturing timber elements for modular and panelized buildings.
• Outdoor and Exposed Timber Structures
  • Employed in bridges, decking, and other environments where weather and biological threats elevate risk.
• Quality Assurance and Trade
  • Provides confidence in product durability for manufacturers, importers, suppliers, and clients throughout the European timber supply chain.

Related Standards

EN 15228:2009 works in conjunction with several key European standards relevant to the durability and strength classification of timber:

• EN 335 - Durability of wood and wood-based products – Definition of use classes
• EN 351-1, EN 351-2 - Classification and sampling for preservative-treated solid wood
• EN 384, EN 408 - Structural timber testing and characteristic values
• EN 599-1 - Performance of preventive wood preservatives
• EN 14080, EN 14081-1, EN 14250 - Product requirements for glued laminated and strength-graded timber
• EN 13501-1, EN 13823 - Reaction to fire classification

Implementing EN 15228:2009 alongside these standards ensures comprehensive compliance, durability, and safety for preservative-treated structural timber in the European market.

Standards Content (Sample)

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Bauholz - Bauholz für tragende Zwecke mit Schutzmittelbehandlung gegen biologischen BefallBois de structure - Bois de structure traité avec un produit de préservation contre les attaques biologiquesStructural timber - Structural timber preservative treated against biological attack79.040Les, hlodovina in žagan lesWood, sawlogs and sawn timberICS:Ta slovenski standard je istoveten z:EN 15228:2009SIST EN 15228:2009en,fr,de01-julij-2009SIST EN 15228:2009SLOVENSKI
STANDARD
EUROPEAN STANDARDNORME EUROPÉENNEEUROPÄISCHE NORMEN 15228March 2009ICS 71.100.50; 79.040 English VersionStructural timber - Structural timber preservative treated againstbiological attackBois de structure - Bois de structure traité avec un produitde préservation contre les attaques biologiquesBauholz - Bauholz für tragende Zwecke mitSchutzmittelbehandlung gegen biologischen BefallThis European Standard was approved by CEN on 7 February 2009.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the CEN 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 translationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, 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.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMITÉ EUROPÉEN DE NORMALISATIONEUROPÄISCHES KOMITEE FÜR NORMUNGManagement Centre:
Avenue Marnix 17,
B-1000 Brussels© 2009 CENAll rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 15228:2009: ESIST EN 15228:2009

Preservative treatment not affecting
strength and stiffness properties of treated timber . 11 A.1 General . 11 A.2 Preservatives types . 11 Bibliography . 12
...