WOOD-BASED PANELS Past, Present and Future
An article by Alastair F Kerr, Director-General, Wood Panel Industries Federation, published in TRADA Timber Industry Yearbook 2000.
Moving into the next millenium provides an ideal opportunity to look back at some of the influences being brought to bear on wood-based panels, and to observe how these influences have and will alter the types of product sold, and also the way in which they are presented to the market place.
Whilst the earlier years of this century saw the development of wet process fibreboards and particleboards, and the commercial market for plywood really began to flourish, arguably the most significant developments influencing the trade today occurred within the last thirty years.
The fundamental composition and character of wood-based panels has not changed significantly since their conception, this being particularly true of plywood, chipboards and wet process fibreboard, such as softboard and hardboard. However, with improving process technology and resin technology, as well as many new finishing techniques, we have seen major improvements in board properties and in addition the introduction of numerous value added variants.
The acceptance of wood-based panels into so many everyday products and applications has been a major achievement and, in respect of the post-war consumer society, chipboard, hardboard and plywood stand out as being major influences.
Moving into the next century, without doubt the one newer panel type which is impacting on the market above all others, is Medium Density Fibreboard (MDF). MDF uniquely cuts across the market of not only other wood-based panels, but has also replaced timber as the preferred material for particular applications. In 1966 the first commercial-scale MDF plant started and by 2000-2001 world production capacity of MDF is projected to be approaching 29 million m3, with European producers accounting for about one-third of this figure. Although these numbers are impressive, world MDF production is still only at the level European particleboard production capacity was in 1998.
Oriented Strand Board, utilising small dimension roundwood thinnings in a manner which can provide impressive strength characteristics, is also emerging as a board with significant growth expectations in the future and has already taken over, in certain applications, from softwood plywood.
To support any market, a system of standards and regulations is needed to provide a framework, which defines products and specifies minimum levels of performance for given characteristics. For many years a system of voluntary national standards has existed and for those involved with wood-based panels the references to BS 1142 (fibreboards), BS 5669 (Particleboard) or BS 1088 (Marine Plywood) will be familiar. As a consequence of membership of the European single market, over the past 10 years this system has been slowly changing so that today, particularly in the area of construction products, most national standards are being replaced by European standards. We are now nearing the point where there will be a mandatory requirement for building products to achieve a minimum standard in respect of certain properties (related to the Essential Requirements mentioned below) before the product legally can be put on the market.
The legal “umbrella” under which this system of standardisation sits is the Construction Products Directive (CPD), which was encapsulated within UK law by the Construction Products Regulation 1991. The CPD has established six essential requirements relating to the performance of Construction works which products must satisfy, namely
Mechanical resistance and stability
Safety in case of fire
Hygiene, health and environment
Safety in use
Protection against noise
Energy economy and heat retention.
Within the European Union anyone putting on the market a building product, including wood-based panel products, must demonstrate that the product (subject to its intended use) will satisfy whichever of these Essential Requirements are relevant to the product. In the case of wood-based panels a single Harmonised Standard (under preparation in 1999) will set out the criteria which have to be met in order to satisfy the CPD.
A significant change from previous voluntary standards is that under the CPD there is a legal necessity for the product manufacturer to demonstrate, through testing, that the product conforms to the mandatory aspects of the relevant BS EN product specification and this may also have to be confirmed by third-party inspection and testing. These mandatory aspects are highlighted in the Harmonised Standard, and products complying with these mandatory minimum specification levels will then be entitled to carry the CE Mark, which is the European symbol indicating conformity to the specified Essential Requirements.
Application of the CE Mark has been declared by the government not to be mandatory in the UK. However, this does not remove the legal obligation to comply with the CPD, and in practice it is likely that all manufacturers will wish to use the CE Mark as an open indication that their products comply and are therefore legally on the market. In most other market territories of the EU (Ireland, Portugal, Finland and Sweden have also adopted a similar approach to the UK), conforming products will bear the CE Mark compulsorily and it is not clear why the UK government decided otherwise. The discrepancy could have the confusing effect that whilst construction products imported from outside the EU will be required to carry the conformity mark in most other EU countries they will not be compelled to do so on the UK market (although of course they must conform to CPD requirements in accordance with the same criteria as products manufactured in the EU).
A separate route by which innovatory products not covered by product standards can obtain the CE Mark would be to apply for a European Technical Approval. These are issued by “Notified bodies”. For building products in the UK these are the British Board of Agrément, BM TRADA Certification and WIMLAS.
Before the CE Mark can be introduced, there are still pieces of the standardisation jigsaw which must be put in place. Notably, a new system of classifying reaction and resistance to fire and associated test methods is still to be concluded. The exact date of implementation is uncertain. However, what is clear is that under the new regime wood-based panel products for use in construction within the EU will have to comply with the Harmonised Standard, and specifiers and users will be legally bound to adopt only those products which do comply. Minimum performance requirements and minimum design characteristic values are also being put into place for the structural (loadbearing) of suitable designated wood-based panels.
The above summary of the regulatory position relates most specifically to wood-based panels marked for use in construction. It has now become recognised by the standardisation bodies, as a result of initiatives taken by the panelboard sector in UK, that simpler forms of quality control and acceptability criteria are required for the non-construction markets, including furniture. The development of new standards for this purpose is in progress, beginning with an Industry Standard for UK and Ireland.
Environmental, health and safety considerations are increasingly influencing the future development of wood-based panels. With a world requirement to optimise resource utilisation, wood panel manufacturers have had to adapt to changing raw materials. This change has favoured particleboard, OSB and fibreboard production, particularly as smaller dimension forest thinnings can be utilised, or, in the case of particleboard and fibreboard, co-products and by-products from other wood industries can be used as well as, increasingly, recycled timber. Research into alternative sources of fibre, including man-made fibre, is leading towards the development of composite products with enhanced properties.
The 1990s in particular have been a decade in which the timber industry has had to demonstrate that its materials were derived from sustainable sources.
The panelboard sector has been involved in the developing activities associated with the certification of sustainable forests and chain-of-custody verification, from the forest through to processing. Panelboard manufacturers in the UK have been working (through WPIF) in common cause with the sawmillers (the UK Forest Products Association), to arrive at a workable certification and labelling system which, whilst based on the policy of the Forest Stewardship Council, does involve changes in approach from the FSC.
An Industry Standard, which will provide for the authentication of processed new and recycled wood as well as an approved labelling system, is nearing completion and will be in use during 2000. Product labels will inform the consumer of the credentials of wood-based panels in terms of the traceability of their wood content to certified forests or verifiable recycled timber.
Panelboard manufacturers increasingly have to address the demands of non-government bodies to provide ever more details as to the environmental, health and safety performance of their products. Life-cycle analysis is developing as a tool for quantifying the inputs and outputs of a process, and initial studies are confirming that wood panel products offer a significant advantage over non-wood materials as a consequence of CO2 sequestration and the carbon sink effect afforded by wood.
Periodically questions pertaining to the safety of products as a consequence of their chemical constituents have to be addressed. This was particularly true of MDF in 1997, following exaggerated and ill-informed scare stories in the national media, which were subsequently demonstrated to be unfounded. However, the incident highlighted the need to provide clear and accurate statements as to the material content and any risks and controls that may arise.
This article has only briefly touched on some of the influences on the wood panel sector, many of which are similar in nature to those affecting the timber industry generally. What is clear is that today and in the future there will be an important role for information providers, such as trade associations and research institutes, as well as product manufacturers to provide clear and accurate information to specifiers and users of these materials.
The Wood Panel Industries Federation, in partnership with the National Panel Products Association, TRADA, TRADA Technology, Building Research Establishment and DETR, is developing a technical manual (Panel Guide: the information is included in askTRADA) which will address all the issues mentioned above and many more, and through the unique association of partners it will cover all the generic wood based panel types.
