Project: Service life and performance of exterior wood above ground

A key issue for the competitiveness of wood is the possibility to control durability, service life, maintenance and life cycle costs for constructions and components where wood is used. Traditionally, durability design of wooden components and structures is based on a mixture of experience and adherence to good building practice, sometimes formalised in terms of implicit prescriptive rules. A modern definition of durability is: The capacity of the structure to give a required performance during an intended service period under the influence of degradation mechanisms. Conventional durability design methods for wood do not correspond to this definition. The development of performance-based design methods for durability and service life requires that models are available to predict performance in a quantitative and probabilistic format for intended use condition. The relationship between product performance during testing and in service performance needs to be quantified in statistical terms and the resulting predictive models need to be calibrated to ensure that they provide a realistic measure of service life, including a defined risk level. The key outcome of WoodExter is a guidance publication with the provisional title “Engineering design guideline for wood in above ground applications”, targeted for specifiers, architects and qualified DIY builders, as a first attempt to introduce the core concept: performance based engineering design in practice for wood and wood-based building components in outdoor above ground situations. Focus is on cladding and decking. Other objectives are to generate new knowledge on: How different climates end-use situations will affect the performance of wood. The role of surface coatings and their interactions with wood. Decay indicators from field tests to produce in-service performance predictions and related input to European standardization. The effect of decay on micromechanical properties of wood. The use of novel methodologies, quantitative real-time PCR Polymerase Chain Reaction (qPCR), for identification and quantification of early decay and conventional Polymerase Chain Reaction (PCR) for identification of early detection of colonisation by blue stain and mould. Additionally, another objective is to develop a systematic approach for performance assessments of cladding and deliver a proforma for that purpose.

Acronym WoodExter
Duration 01/10/2007 - 28/02/2011
Website visit project website
Call JC1

Project partner

Number Name Role Country
Vienna University of Technology Austria
Technical Research Centre of FI Finland
Georg-August-University Göttingen Germany
Norwegian Forest and Landscape Institute Norway
Holzforschung AT, ATn Forest Products Research Society Austria
Technological Institute for Forest Cellulose, Construction-wood and Furniture France
Lund University Sweden
Building Research Establishment Ltd United Kingdom
SP Technical Research Institute of SE Coordinator Sweden
Ghent University Belgium