Wood protection standards

Wood protection standards

The right choice and use of wood preservative or preservative-treated wood is of utmost importance, as it determines the life span of your wood product or building, as well as the effects of the protected wood on people and the environment. A preservative that may be effective in protecting (covered) wooden roofing may not be equally effective in protecting wood intended for outdoor use, for use in contact with running water or soil (possibility of leaching of the preservative, ineffectiveness against organisms present), for use in other climatic zones (e.g., possibility of termite attack) or even for use in seawater (possibility of attack by marine pests). Only few preservatives effectively protect wood against all wood pests.   

A good preservative should have the following properties: 

• proven effectiveness and widest possible range of applications; 
• deep wood penetration, and non-leaching feature when exposed toto precipitation; 
• evenly distributed throughout the cross-section of the wooden element; 
• doesn’t have strong odor, 
• when used properly, it is not harmful to humans, animals or the environment; 
• does not increase the flammability of wood; 
• enables further treatment of the wood (e.g., surface coatings). 

When choosing a wood preservative, it is therefore essential to make sure that it is effective, and that the chosen preservative is used correctly or that the wood protection process is carried out in the correct way. In particular, the amount of wood preservative applied must be taken into account (in accordance with the manufacturer’s recommendations) and the depth of penetration of the wood preservative shall be appropriate for the intended use. When checking the effectiveness of the preservative and/or the application process, reference may be made to the applicable international standards (CEN, ISO, ASTM, etc.). Only choose preservatives that are demonstrably compliant with the applicable standards and proven to be effective for your intended use (testing by independent institutions). When preparing major projects and project documentation, we recommend that you consult experts in the field of wood protection (e.g., Department of Wood Engineering, Faculty of Biotechnics, University of Ljubljana) who can help you to choose the relevant standards for your project.

Some of the more important standards in the field of wood protection: 

EN 335:2013: Durability of wood and wood- based products – Use classes: definitions, application to solid wood and wood-based panels 

EN 350:2017: Durability of wood and wood-based products – Testing and classification of the durability to biological agents of wood and wood-based materials 

EN 460:1995: Durability of wood and wood-based products – Natural durability of solid wood – Guide to the durability requirements for wood to be used in hazard classes 

EN 599-1:2009+A1:2014: Durability of wood and wood-based products. Efficacy of preventive wood preservatives as determined by biological tests – Part 1: Specification according to use class 

TS CEN/TS 15083-1:2006: Durability of wood and wood-based products – Determination of the natural durability of solid wood against wood-destroying fungi, test methods – Part 1: Basidiomycetes 

EN 152:1996: Wood preservatives – Determination of the protective effectiveness of a preservative treatment against blue stain in wood in service – Application by surface treatment 

EN 46-1:2010:Wood preservatives – Determination of the preventive action against recently hatched larvae of Hylotrupes bajalus (Linnaeus) – Part 1: Application by surface treatment (laboratory method)Hylotrupes bajulus (Linnaeus) – 1. del: Larvicidial effect (Laboratorijska metoda) 

EN 84:2002: Wood preservatives – Accelerated ageing of treated wood prior to biological testing – Leaching procedure 

ENV 1250-2:2004: Wood preservatives – Methods for measuring losses of active ingredients and other preservative ingredients from treated timber – Part 2: Laboratory method for obtaining samples for analysis to measure losses by leaching into water or synthetic sea water 

TS CEN/TS 15119-1:2008: Durability of wood and wood-based products – Estimation of emissions from preservative treated wood to the environment – Wood held in the storage yard after treatment and wooden commodities exposed in Use Class 3 (not covered, not in contact with the ground), and wooden commodities exposed in Use Class 4 or 5 (in contact with the ground, fresh water or sea water) – Laboratory method 

EN 275:2004: Wood preservatives – Determination of the protective effectiveness against marine borers 

TS CEN/TS 12037:2005:Wood preservatives – Field test method for determining the relative protective effectiveness of a wood preservative exposed out of ground contact – Horizontal lap-joint method 

Becker’s method (1969): : Termiticidal activity of the preservative  

At Silvaprodukt, we make sure that our products and services comply with wood protection standards and that their effectiveness is regularly tested by independent institutions, such as the University of Ljubljana and other independent institutions abroad.   

More standards in the field of wood protection can be found on the website of the  Slovenian Institute of Standardisation..