“Knockouts” found in Weyerhaeuser TJI I-Joists are quick and convenient 1 1/2” round holes spaced 12” on center. They are perforated in to the TJI and easily removed with a hammer. Placement of these “Knockouts” does not affect placement of other holes or interfere with bearing points. These unsung heroes of the job site are great for trades looking to speed up productivity by taking the “guess work” out of hole placement.