Eco Priority Guide: Timber and Wood Products

 

Overview

Forest management practices, particularly with regard to protection of biodiversity, remains as the most significant sustainability issue for wood products . Plantation management is coming under increasing scrutiny, as are related silvicultural issues, such as the use of genetically modified tree crops.

The use of wood products has the potential to lock carbon and reduce energy consumption relative to many other materials, however many wood products today are composites or use synthetic chemicals in their manufacture or fixing which have their own environmental loads (e.g. preservatives toxicity in disposal).

The sustainability of forest management in many areas of Australia and overseas continues to be subject to vigorous scientific and community debate. Many imported tropical timbers are sourced from uncontrolled illegal logging in Asia, although it is almost impossible to currently track. The 2001 State of the Environment Report found that in Australia many biologically significant ecosystems had not been protected under the Regional Forest Agreements and that the efficacy of forest management prescriptions remained to be determined. Major conservation groups remain concerned that Australia’s conservation reserve system is not adequate and that forests are being significantly degraded through logging practices. Government and Industry consider the Regional Forest Agreement (RFA) process to have delivered a comprehensive reserve system and resource security to the industry.

A principle emerging issue for specifiers is the development of third party certification schemes including the Forest Stewardship Council (FSC) and Australian Forestry Standard (AFS), which seek to provide greater confidence in claims of sustainability. Both offer Chain of Custody Certification (CoC), providing commercially for the first time a paper trail for timber from the point of extraction to point of sale.

A principal barrier to the future reuse or recycling of wood products, an essential characteristic of any sustainable material, is the use of adhesives and other non-mechanical fixing techniques often preventing reuse or recycling.

 

Eco-Priorities

For the following products, key associated impacts are:

Priority Order	Solid untreated timber	Laminated timber products	Wood panel products	Preservative treated timber	Wood composites
1	Habitat	Habitat	Habitat	Habitat	Varies depending on constituent components
2		Health	Health, Toxics	Toxics, Health
Red Light?*	Ref Timber Tech Note	Ref Timber Tech. Note	Ref Timber Tech Note	Ref Timber Tech Note	Ref Timber Tech Note
Example	KD HW	Plywood, laminated veneer lumber (LVL)	MDF, chipboard	CCA, LOSP, Tanalith E, Naturewood™	e.g. wood-plastic composites

*'Red light’ issues are issues that are high-concern and are an eco-design basis for not using the product.

GHG: production of greenhouse gases, ozone-depleting chemicals

Habitat: destruction or an erosion of Habitat and/or biodiversity values

Toxics: toxic and/or persistent and/or bioaccumulative emissions to the environment

Health: products or emissions during production or use that directly impact on human health

Resources: the use of raw resources e.g. oil, metal ores.

 

Making a Decision

Commentary

• Specify what you want rather than what you don’t want.
• Use reused and recycled timbers where possible
• Preference third-party certified products with chain of custody, e.g. Forest Stewardship Council (FSC), whether local or imported.
• ‘Certification’ or other market claims without Chain of Custody (CoC) offer limited scope for independent auditing and should be treated with caution.
• Use local timbers in preference to imported timbers, except where imported timbers have superior certification.
• Specify smaller section timbers and sizes to optimise for plantation and regrowth timbers
• Use feature grade rather than ‘clear’ or select grade timbers. This reduces wastage and facilitates the use of younger timbers.
• Do not over design. Use high value timbers & veneers in long-lasting applications where they will be appreciated.
• Start with the end in mind: design to allow for reuse and recycling. Use mechanical fixing only if reuse or recycling is likely to be possible.
• Minimise toxicity. Not all glues and preservatives are created equal. Use lowest impact option for the application.
• Be aware of differing meanings in specification. Terms like ‘plantation’ may be used in instances that do not strictly fit, e.g. the Federal definition is 'intensively managed stands of trees of either native or exotic species, created by the regular placement of seedlings or seed' (Walker-Morison, 2003).

Decision-Making Checklist

1. Does a thing have to be made or used? If so, does it create a net benefit?
2. Fate: Start with the end in mind. If the product is not reusable, fully biodegradable or highly recyclable at the end of life, or facilitating these activities, its not sustainable.
3. Energy: What will the product’s likely net energy balance be over its life? Will it save more energy than it uses?
4. Durability: Does the product embody an appropriate level of durability for its accessibility, criticality and maintenance profile?
5. Biodiversity: Is there a chance that the product has had a negative impact on biodiversity? Erosion of biodiversity is a one-way street.
6. Toxicity: Is the product toxic and or persistent in the environment at any stage in its life cycle? If so, don’t use it.
7. Resources: Does the product use rare resources/ create a net negative flow of resources (e.g. poor maintainability/ high maintenance requirements)
8. Is the product socially sustainable?
9. Does the product, or its use, contribute to delivering synergy benefits in other building systems?

Source: Adapted from Andrew Walker Morison

 

Quick Guide

Solid untreated lumber
For Renewable potentially highly sustainable resource Low embodied energy (2-4MJ/kg) High-strength to weight ratios achievable Potentially high inherence durability Wide range of appearance and physical characteristics Potentially reusable, recyclable	Against May be sourced from poorly managed forests or plantations with adverse habitat, biodiversity, or toxicity impacts
Laminated Timber products
For Excellent structural characteristics High efficiency use of timber Potentially reusable, recyclable	Against Options for reuse, recycling, or waste to energy recovery at the end of life may be limited by glues used Some glues are highly durable and do not readily biodegrade Higher embodied energy typically 10-11 MJ/kg
Wood panel and derivative products
For Cost effective Use of low value wood or waste-wood product	Against Relatively high embodied energy as adhesives typically have 20-30 times as much embodied energy (kg for kg) as timber. Panel products typically have embodied energy of 8-10MJ/kg. Adhesives used for interior grade products typically associated with emissions of formaldehyde which can have adverse health impacts Options for reuse, recycling, or waste to energy recovery at the end of life may be limited by glues used
Preservative treated Timber
For Allows the use of fast-growing low value timbers species in high-hazard applications Allows the substitution of timber for other materials e.g. steel and concrete, which have their own significant environmental impacts	Against Preservative treatments can be toxic to humans and the environment Options for reuse, recycling, or waste to energy recovery at the end of life may be severely constrained by chemicals used Preservative chemicals and significant levels of emissions associated with their production, and embodied energy Long-term health and environmental impact is of preservative chemicals are still poorly understood
Wood composites
For Allows the creation of products with desirable and unique characteristics including wood appearance and outstanding durability	Against Options for reuse, recycling, or waste to energy recovery at the end of life may be severely constrained by coproducts used Potentially higher embodied energy depending on co-products used

Note: embodied energy figures (Lawson, 1996).

 

Selected Links and Resources

Refer to the ecospecifier Knowledge Base  -  Timber & Wood Products Technical Guide section for information on;

• Overview and statistics on sector
• Embodied energy figures
• Relevant standards and eco-assurances
• Less-toxic products & alternatives
• Case studies
• Recommendations
• Further links and references

 

The following resources provide general information from an international conservation perspective;

• For a global forest issues perspective and conservation information the World Resources Institute web site is outstanding.
• Also excellent is Global Forest Watch, with some truly horrifying images of estimated historical oldgrowth (‘frontier’) forests and current remnant frontier forests.
• Australian Department of Agriculture, Fisheries and Forestry (AAFF)
• The federal resource on the Australian Forestry Standard (AFS)
• Forest Stewardship Council - the international agency web site
• National Association of Forest Industries - the peak industry body with regard to a broad range of issues including certification
• Certifiedwood.org - A site that has both industry and conservation group interests represented and provides an excellent introduction to certification as well as a powerful search tool for timbers and distributors of certified forest products globally:
• FAO - for a global UN perspective and a wealth of general forestry facts and figures:
• Friends of the Earth UK Good Wood Guide - a global guide to forest and timber species conservation status from a leading international conservation group in this field. Follow the links from the home page and search for ‘Good Wood’.
• Forest Conservation Portal - perhaps the leading global compendium of articles, information access and links to forest-related conservation material:
• Alaskan Conservation Foundation - for a local perspective on forest status in Alaska where some of our Oregon comes from this excellent site has both slide shows and audio tours.
• Rainforest Information Centre Good Wood Guide (Australia) - for a domestic Conservation Group perspective an thorough resource.
• EU Wood Products - for a conservation perspective on European wood products.

 

Further Information

For more detailed information on this topic contact subscribers@ecospecifier.org

 

References

Lawson, B. (1996). Building Materials, Energy and the Environment. Sydney, Royal Australian Institute of Architects.

Walker-Morison, A. (2003). TIMBER & WOOD PRODUCTS: APPLICATIONS AND ESD DECISION MAKING. Environment Design Guide. Melbourne, Building Design Professionals Association.