Genesis 6:14-16

Young's Literal Translation

¹⁴ `Make for thyself an ark of gopher-wood; rooms dost thou make with the ark, and thou hast covered it within and without with cypress;

¹⁵ and this [is] that which thou dost with it: three hundred cubits [is] the length of the ark, fifty cubits its breadth, and thirty cubits its height;

¹⁶ a window dost thou make for the ark, and unto a cubit thou dost restrain it from above; and the opening of the ark thou dost put in its side, -- lower, second, and third [stories] dost thou make it.