Sawn Timber

For problems arising with the quality of pallet and packaging timber such as bluestain or white moulds, go to the page TREATMENTS/MOISTURE

There is no single wood quality grading system in Euope, a surprising fact that frustrates those new to the industry and makes understanding the timber supply that much more difficult. If buying from British or Irish mills there is less of a problem, fewer species and no language problem helps but packaging timber buyers requiring large volumes from overseas are obliged to make their own ad-hoc arrangements with individual sawmills for future supply. They will need to agree acceptable visual quality, amount of wane, inclusion of weaker species, dimensions, accuracy of sawing, moisture content and any use of chemical antistain solutions.

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French maritime pine pallet boards

Wood is a natural material and where quality grading systems for wood exist they were locally developed and widely used long before the advantages of international standardisation were recognised. This is quite unlike the wide ranging ISO agreement on pallet plan sizes where the advantages of international standardisation are well recognised – they either fit freight containers or they don’t. Even outside of packaging there is no international system for specifying wood grades for end use. There are well understood commercial systems that have been in use for many years, but they are only national, or at best used by only a handful of countries, such as Scandinavia. More recently in Europe it has become commonplace to specify ‘mixed grade’ which means a mix of 1st class (square material) with an agreed amount of 2nd class (material with some wane). This appears to be happening with both softwood and hardwood purchases and is leading to considerable debate as to what is the acceptable mix eg. 80/20 (wane free/wane) and what is the acceptable amount of wane on a permitted piece, etc.

The Baltic area is important for timber used in pallets and packaging, but the term widely used by the pallet industry of ‘Baltic mixed’ can create confusion because of the increasing use of the supply industries new ‘mixed grade’ term. ‘Baltic mixed’ a term long used by the pallet industry refers to a mix of hardwood and softwood species. This can create quite different problems, for example one of safety. What is ‘Baltic mixed’ as so often quoted? It is in fact a random mix of strong species mixed with weak species and a pallet designer/specifier can hardly work with that, since the weakest in the mix have only half the strength of the strongest. However, alongside this, much commercial Baltic softwood is highly sought after for top grade pallets and packaging, such as 5th grade red/whitewood.

Adding to the weaknesses in such a species mix (apart from high quality rental or exchange pallets) whitepallets (non-rental) are usually built with a small safety factor. It is therefore difficult to have any confidence in a pallet’s strength if Baltic mixed has been used. For safety, the manufacturer must assume that it includes random amounts of weak species and adjust pallet board thickness upwards to compensate. The Baltic area produces some of the highest quality, strongest softwoods anywhere but unfortunately if these are randomly mixed with the weakest, the perceived and actual value of Baltic timber for heavy-duty pallets is much less than it could be.

In 1999 a grading system for European packaging wood was published as EN 12246: Quality classification of timber used in pallets & packaging which contains a new system specifying two packaging qualities, P1 and P2. To fully understand EN 12246 it needs to be read alongside companion document EN 1310: 1997: Round and sawn timber - Method of measurement of features. However, in reality EN 12246 has had hardly had any effect on European packaging timber markets, agents or buyers. Not including the newer ‘mixed grade’ method of quality sorting of timber, outlined above, Datasheet 71e summarises the older, all different, occasionally used, Scandinavian, Canadian, Russian and USA, visual grading systems.

There has always been a market for strength graded timber for house building in the UK, Germany and Scandinavia. Strength grading has now grown and includes most EU states. However this applies to high quality timber for house building and is above the prices pallet and packaging markets expect to pay, so is of little interest. A further problem is that strength graded timber is not available in thicknesses below 35mm.

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PDF71h Baltic hardwoods and softwoods in pallet construction (PDF 18kb)
PDF72j Sawn softwoods of NORTH AMERICA suitable for pallets and packaging (PDF 27kb)
PDF78b Natural Durability of Timbers used in pallets and packaging (PDF 25kb)
PDF79a Permissible bark and wane in wood pallets and packaging (PDF 34kb)
PDF79e Wood quality grades for pallets and packaging - Summary of EN 12246 (PDF 26kb)
PDF80i INDEX OF EUROPEAN WOOD GRADING standards and documents (PDF 24kb)
PDF86e Sustainable sources for timber pallets and packaging (PDF 20kb)
PDF89g Wood pallets & packaging used in sub-zero temperatures (PDF 18kb)
PDF98d Timber embrittlement through high kiln temperatures (PDF 18kb)
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