What is the minimum end bearing requirement for masonry lintels over windows?

The minimum end bearing requirement for masonry lintels over windows is 4 inches for both windows and doors. This requirement ensures that the lintel has adequate support to bear the load above the opening effectively. A 4-inch bearing provides sufficient engagement with the masonry units on either side of the window or door, which is critical because inadequate bearing can lead to structural failure or cracking in the masonry. This standard helps maintain the integrity and stability of the building's façade, ensuring that the lintel can support the weight of the wall materials and any other loads that may be present.