LIB88s Web Holes

Holes may be cut in the LIB webs to accommodate electrical wiring, plumbing lines and other utilities.

  • NEVER cut, notch or bore through LIB flanges except for docking to length
  • NEVER cut holes larger than 40mm in a cantilever span
  • NEVER cut any holes within 150mm of the edge of a support
  • All holes should be centred on the centre line of the beam
  • All holes shall be cut in a tradesman like manner and not over cut
Holes in Joists

Web Hole Selection Tables

  1. Identify the column that meets or exceeds the required hole size.
  2. Identify the LIB joist being used.
  3. Scan horizontally until you intersect the column that contains the hole size required. This value is the required minimum distance from the edge of the hole to the inside face of the nearest support.
  4. Multiple holes require spacing of twice the length/diameter of the largest hole.
  5. A MAXIMUM of three holes per span except diameters 60mm or less, or squares 50mm or less.
  6. Data applies for joists not supporting offset load bearing and with a maximum of 1.8kN concentrated live load.
  7. Distances are based on the maximum span of each joist.
  8. Nelson Pine Design can be used to calculate allowable web hole sizes for each situation.

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