Is the idea that if the crack does get worse, it propagates towards the hole then hopefully stops there?
No, you want the end of the existing crack to be within the diameter of the hole. Typically, people centre the drill on the end of the crack, but you don't need to worry about nailing it precisely. I'd probably drill it min. 3mm/⅛" up to 5mm/3/16"
No, you want the end of the existing crack to be within the diameter of the hole. Typically, people centre the drill on the end of the crack, but you don't need to worry about nailing it precisely. I'd probably drill it min. 3mm/⅛" up to 5mm/3/16"