Lumber volume calculator: cubic metres of a batch

Multiply thickness, width and length in millimetres and divide by 10⁹ — that gives the volume of one piece in cubic metres. Multiply it by the number of boards per pack and by the number of packs.

Nominal — the size written in the specification. Actual dimensions after drying are 1–3 % smaller, but batch volume and price are calculated from the nominal size, otherwise the buyer's and the seller's figures will not match.

Straight multiplication will not work because the width varies. The average width is used, measured at mid-length without bark. For a whole batch the stack is measured and multiplied by a solid-volume coefficient.

A solid cubic metre is the wood itself; a stacked one is the volume of the pile including the gaps. To convert, multiply the stacked volume by the solid-volume coefficient: 0.85–0.95 for packed edged lumber, 0.62–0.72 for unedged boards, 0.4–0.6 for slabwood.

It depends on the section and the number of boards. Calculate the volume of one board and multiply by the pieces per pack: 44 boards of 50×150×6000 mm, for example, give 1.98 m³.

Three common reasons: the calculation used actual instead of nominal dimensions, the batch contained a different grade or length than declared, or the volume was measured by the stacked method with a different coefficient.