89. A hole is required for piping 4 inches from the bottom of a 2x10 joist that is 12 feet long. The hole is 2 feet from the end of the joist. The maximum allowable size of this hole is approximately
Answer: C
The maximum allowable size of the hole is approximately 3 inches.
In this scenario, the maximum allowable size for the hole in the joist is determined by structural guidelines which allow for a hole that does not exceed 3 inches in diameter given the specified dimensions and location.
A) 1 1/2 inches
This option is incorrect because a hole size of 1 1/2 inches is too conservative and does not utilize the maximum allowable size based on standard structural guidelines. While it is a safe size, it undercuts the potential limit of 3 inches.
B) 2 inches
Although a 2-inch hole is permissible, it does not represent the maximum allowable size. While it may be structurally sound, it falls short of the maximum limit of 3 inches that can be safely accommodated in this specific context.
C) 3 inches
This option is correct as it meets the maximum allowable size for the hole based on the joist's dimensions and placement. Structural guidelines permit a hole up to 3 inches in diameter when located 4 inches from the bottom and 2 feet from the end of the joist.
D) 3 1/2 inches
This option exceeds the maximum allowable size for the hole, making it structurally unsafe for the specified joist. A hole this size could compromise the integrity of the joist, which is why it is not permissible.
Conclusion
The correct answer of 3 inches is definitive as it aligns with structural guidelines for drilling holes in joists of this size and configuration. Options A and B are smaller than the maximum allowable size, while D exceeds it, risking structural integrity. Thus, C stands out as the only suitable choice.