Make for yourself an ark of gopher wood; you shall make the ark with rooms, and shall cover it inside and out with pitch. (Genesis 6:14)On the surface level, the ark belonged to Noah— it was Noah's ark. But on a deeper level, the earth is the LORD's and all it contains. All that the earth contains includes Noah's ark. The ark belonged to Noah in the sense that he built it, but in another sense, the ark belonged to God— God is the one who made the wood, which Noah used to make the ark.
If it were not for the fact that Noah found favor with God, Genesis 6:14 would not exist. If Noah had not found favor with God, there would have been no ark; there would have been no future for humanity. However, as is stated in Genesis 6:8, Noah did find favor with God. This leads to an interesting question: Since Noah found favor with God, was God "required" to save Noah from the flood?
Throughout history, believers have faced many tribulations. Believers have faced torture and martyrdom— they have faced the consequences of their sin. Moses, for instance, was not allowed to enter the promise land. And why was he not allowed to enter? ...because of sin that was in his life.
Similar to Moses, Noah was not totally free from sin. Noah was not perfect. God would have been perfectly just to let Noah perish in the flood. However, if Noah had perished in the flood, he would have been cast into hell. This is because that without Noah, Christ would not have come to the earth (for Jesus was born many generation after Noah). Without Noah, the descendants of Adam would have come to an end. God never would have become flesh in order to atone for sin. All of humanity would have been blotted out.
God's Ark Which Noah Built (Part 2) - Genesis 6:14
Noah Found Favor In The Eyes Of The LORD - Genesis 6:8
The Pre-Flood World Soon To Be Blotted Out - Genesis 6:7
State of the World (2948 BC): Noah's Birth - Genesis 5:28
Man in the Image of Man - Genesis 5:3