Use this workshop calculation to turn measured dimensions and the selected construction convention into a cut, spacing, fit, or material-planning value.

Panel length (mm)

Panel length in millimeters.

Recommend a biscuit spacing of 100 mm for panels up to one meter and 150 mm for longer panels. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Recommended spacing (mm)

Recommended spacing between biscuits in millimeters.

• Nominal dimensions, kerf, moisture movement, hardware clearances, wall squareness, and manufacturer instructions can change the required shop dimension. Measure the actual assembly and test critical joints on scrap before cutting finished material.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Complement the calculated dimension with a physical story stick, dry fit, or full-size layout. Follow the hardware, coating, adhesive, or machine manufacturer's limits where they differ from a rule of thumb.

• Ceiling Panel Expansion Gap Rule

  Recommend the tongue-and-groove ceiling panel expansion gap as 8 mm from 4 m field length and 5 mm below.

• Biscuit Size Lookup

  Look up the width, height, and thickness of a standard biscuit size.

• Biscuit Slot Depth Lookup

  Look up the standard joiner plunge depth for size 0, 10, and 20 compressed-wood biscuits.