Genesis 6:16-18

16 You are to make an opening for daylight in the ark eighteen inches below its roof. Put a door in its side; and build it with lower, second and third decks.

17 “Then I myself will bring the flood of water over the earth to destroy from under heaven every living thing that breathes; everything on earth will be destroyed.

18 But I will establish my covenant with you; you will come into the ark, you, your sons, your wife and your sons’ wives with you.