What should not exceed 1/3 of the depth when boring?

When boring holes in structural members like joists, it is crucial to adhere to safety and structural integrity guidelines. The correct guideline indicates that the size of the hole should not exceed 1/3 of the depth of the joist. This limitation is based on the need to maintain the structural performance and load-carrying capacity of the joist.

Boring too large of a hole compromises the member's ability to carry weight and distribute loads effectively, which can lead to structural failure or decreased performance of the building. Therefore, keeping the bore size within 1/3 of the joist depth ensures that the structural integrity is preserved, allowing for safe construction practices.

Other options concern the dimensions of different structural components but do not have the same critical implications. For example, joist width, stud depth, and plate thickness have their own guidelines, but the 1/3 limitation specifically applies to joist depth when it involves boring to maintain safety and support in construction.