TRADA Technology’s work on material useage in the timber sector is one of a range of Biffaward-funded studies looking at “resource flow” throughout the UK economy. These are known as ‘mass balance studies’ and they determine the amount of material that enters and leaves an industry over a set accounting period, usually a year.

While we have detailed information on the levels of finances that flow though the economy, there is relatively little information on resource or material flow. But this data is of fundamentally important to cost-effective management of resource flows. It becomes even more important at the stage when resources become ‘waste’. Diverting waste from landfill is a prime target, but to do that, companies need to understand where waste is generated and what the alternatives to landfill might be.

With the introduction of landfill tax, traditional and often preferred means of disposal are becoming more expensive. Many of the materials generated from wood processing do have a demand and ready markets. Materials that cannot be recycled, recovered or reused, for whatever reason, become waste. In the interest of greater efficiency and sustainability, one challenge facing the timber industry is to move to a position where material traditionally considered as waste can be considered as a resource with a value and a demand.

Mass balance provides a method for assessing resource flow by taking account of the material within a system at the beginning of an accounting period (initial stock) and measuring the material that enters and leaves the system during the accounting period.

Sector reports

Specific mass balance reports were completed for the following sectors: joinery; furniture; food packaging; pulp and pulp logs; and construction. In addition, a summary report was completed, to present a combined timber mass balance for the UK as a whole.

Compared with other major industries in the UK, the wood-using industries have little robust data to quantify wood-based products consumed and manufacturing residue generated.

Data collection is made difficult by the fact that the timber industry is so diverse, including as it does the production of sawn timber and panel products, through secondary processing (furniture and joinery), right down to the end use application of various forms of wood in construction. It also contains a high proportion of small operators, particularly true of the joinery sector, which employs an estimated 45,000 people, yet companies typically average fewer than 10 employees.

In terms of annual timber flow through the UK, the study suggests that the joinery, packaging and pulp sectors each account for around 10%, the furniture sector 22%, but by far the most significant user of timber and wood products, accounting for 46% of the total, is the construction industry. This is not surprising, as the sector represents 8% of national GDP and 10% of the workforce. Analysis of Office of National Statistics data suggests that in 2002, four million of the six million tonnes of softwood entering the UK went into construction (along with one-third of UK home produced softwood, providing about 15% of the sector’s needs and that proportion is set to grow).

Construction waste

The study also suggests that the construction sector generates approximately 1.1 million tonnes of woodwaste, of which more than 70% consisted of softwood and about 12% of plywood and chipboard.

Much of this waste occurs when material is cut to length on site. Here, it is tempting to order in oversized material and cut it down, rather than risk delivery of undersized material that will have to be re-ordered. The nature and proportion of woodwaste is very much dependent upon the type of construction in question, however. In many projects, prefabricated wood may be used, leading to minimal quantities of wood being cut on site, with correspondingly low levels of waste.

Unlike other sectors of the timber industry, the construction sector does not have permanent static centres for production, but rather transient centres, which move on once a project has been completed. Construction sites, particularly in urban areas, have space restrictions and may not have the capacity for waste segregation. This may explain why the largest single disposal outlet was identified as waste management companies.

For the joinery sector, on the other hand, at nearly 25%, the study suggested that the largest single disposal route for process waste is in animal bedding – much joinery waste is relatively high quality softwood. The next option, at just over 15%, was identified as fuel for the production of heat and/or power on-site, allowing many operators to reduce both disposal volumes and therefore costs, as well as making savings on heating costs.

The joinery sector generates relatively high volumes of process waste, which may easily exceed 30% for hardwood in particular. It obtains most of its wood in the form of raw timber, mainly imported softwood, rather than as manufactured products. The sector overwhelmingly serves the domestic market, where it was suggested that some 75% of production goes into the construction sector.

Interestingly, the next largest recipient of joinery products, identified at 21%, was the joinery sector itself. This may be explained by manufacturers producing components for other companies within the sector.

It is likely that in future, joinery manufacturers will face increasing competition from countries with low labour costs. In terms of mass balance, such a trend would reduce the volume of wood being imported into the UK in addition to reducing the volume of process waste being generated here.

Sustainability issues

Another key aspect of the mass balance study was to determine the quantity of raw material that originated from a sustainable source, with a view to encouraging individual companies to investigate increasing their purchasing of sustainably produced material.

Such information, combined with mass balance data, will make it possible to assess the environmental demands imposed by each sector, and help to forecast future pressure on forests for raw materials.

It is encouraging to note that in construction, more than 80% of respondents believed that they purchased sustainably, while the supporting market research for the joinery sector suggests that about 70% of their raw materials, they believe, come from sustainable sources.