Proper Hole Placement and Dimensions for Drainage
- Where gusset plates are used, generously cropped corners provide for free drainage. When cropping gusset plates is not possible, holes at least 1/2” (13 mm) in diameter must be placed in the plates as close to the corners as possible.
- To ensure unimpeded flow of solutions, all stiffeners, gussets, and bracing should be cropped a minimum of 3/4” (19 mm).
- Provide holes at least 1/2” (13 mm) in diameter in end-plates on rolled steel shapes to allow molten zinc access during immersion in the galvanizing bath and drainage during withdrawal.
- Alternatively, holes at least 1/2” (13 mm) in diameter can be placed in the web within 1/4” (6 mm) of the end-plate. To facilitate drainage, end-plates should have holes placed as close to interior corners as possible.
