Kiln Capacity Calculator
Wood volume per charge from stack size, board thickness and sticker thickness (AH-188).
Enter the kiln stack dimensions (length × width × height in metres), the average board thickness (mm) and the sticker thickness (mm, default 19). The tool returns the wood volume in cubic metres and in board feet per charge, plus the wood fraction of the stack (t / (t + s)) and the stack-fill factor used.
FAQ
What is the right sticker thickness?
19 mm (3/4″) for most hardwoods up to 50 mm thick; 25 mm (1″) for thicker stock or for softwoods that need more airflow. Thinner stickers give more wood per charge but risk uneven drying (the sticker imprint stays wetter); thicker stickers waste kiln volume. For 25 mm boards and 19 mm stickers, expect about 57% wood in the stack — that's a kiln utilisation of 0.57 m³ of wood per m³ of stack.
Why does the fill factor matter?
The fill factor accounts for losses: end gaps, side gaps between boards of different widths, slightly off-square stacks, and the fact that stickers aren't full length. 0.9 is a reasonable default for well-stacked hardwood charges; 0.85 for rougher softwood stacks. The NC State extension recommends measuring actual charge weight and comparing to the geometric volume to back out a fill factor for each kiln.