Finnforest UK

HOLE CONSTRUCTION

FINNJOIST ROUND HOLE DISTANCE CHART 
 
Distance from edge of hole to inside edge of supports in mm.

  Coloured areas indicate minimum distance to support edge for holes greater than 38mm.
        For Notes see below.

Notes for Finnjoist hole construction:

1.   DO NOT CUT OR NOTCH FLANGES
2.  Cut holes carefully.  DO NOT over-cut.  DO NOT cut
     flanges.  ROUND CORNERS OF RECTANGULAR
     HOLES WHEN POSSIBLE.
3.  Holes must not be closer than 8mm from I-Joist
     flange.
4.  For rectangular holes, avoid over-cutting the corners.
     Slightly rounding the corners is recommended. 
     Starting the rectangular hole by drilling a small
     diameter hole in each of the four corners, and then
     making the cuts between the holes, will minimise
     damage to I-Joist.
5.   Minimum distance for holes greater than 38mm
     diameter is 300mm from supports.
6.  Do not cut holes larger than 38mm in a cantilever.
7.  The length of uncut web between holes must be at
     least twice the length of the longest adjacent hole
     dimension.
8.  Pre-punched knockout may be ignored when
     calculating distances between holes.
9.  Hole locations and sizes are based on uniformly,
     domestic loaded I-Joists.  For other conditions
     please contact your Finnforest engineered wood
     product distributor.

FINNJOIST RECTANGULAR HOLE DISTANCE CHART 

Distance from edge of hole to inside edge of supports in mm.