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42 TECHNOLOGY SEP/OCT 2025 FDM ASIA | www.fdmasia.com

Table 3. Green, Red Oak 4/4 Lumber Prices, per 1000 linear regression was performed to determine the break-even
bdft (HMR 2024)
operating cost, e.g., the operating cost such that total profit
was $0.00 (Eq. 1).
As shown in Table 4, the break-even operating cost for

the 12 MMBF sawmill was found to be $2010 per hour.

Table 4. Break-even Operating Cost, Production Times,

and Costs for 12, 8, and 4 MMBF Sawmills

SmurfitWestrock located in Covington, VA reported that
the average price for hardwood chips, bark, and sawdust
was $25, $17, and $17 per tonne, respectively, delivered
FOB to the mill.
To estimate shipping costs, a local trucking company was

contacted for a quote to transport residue products to the This analysis was repeated for 4 MMBF and 8 MMBF
SmurfitWestrock mill in Covington, VA from a hypothetical annual sawmill production volumes. The break-even operating
sawmill 50 miles away. cost for the 4 MMBF and 8 MMBF sawmills was determined
The quoted price depends on the number of trailers to be $670 and $1337, respectively (Table 4).
required to be parked at the mill to collect the residues and Table 4 shows additional results from these operating cost
the number of loads per day delivered to the mill. examinations. Note the difference in processing times (hours
Weiss quoted a price of $17 per tonne for the residues to process 1000-log sample, Table 4) and estimated annual

to be transported based on a mill volume of 12 MMBF. This operating costs (Table 4) among the different annual production
example indicates that residue products are not currently a volumes. Based on Eq. 1, there is a linear relationship based
profitable aspect of sawmill operation. on production volume (MMBF) between the values presented
However, sawmills can at least be break-even with respect in Table 4.
to residues and avoid tipping/disposal fees at landfills.
Statistical Methods
Operating Cost Calculations Using Levene’s test, variances between operating cost,
Given established current market prices (at the time of analysis) log cost, and lumber and residue value groupings were found
for logs, lumber, and residue products, and known annual not to be equal (α = 0.05).

production volumes and operating hours, a break-even hourly Thus, a non-parametric approach was required to analyse
or annual operating cost can be calculated (Eq. 1). the differences among the cost and price groupings. To
To calculate the operating cost, the 1,000-log sample determine what degree of change in one or more of the cost
was processed with LORCAT using the processing settings, factors (operating cost, log cost, and lumber and residues
log, lumber, and residue prices that were discussed earlier. price) resulted in a significantly different profit (loss or gain)
For the 12 MMBF sawmill, five simulations were performed with respect to the break-even point.
using hourly operating costs of $1900, $1950, $2000, $2050 The Aligned Rank Transform (ART) statistical test was

and $2100. used in conjunction with R. ART allows for the analyses of
Based on the reported total profit for each analysis, multi-factor designs while traditional non-parametric tests