All live in apartments to save the environment?

If all human beings lived in a 5-story apartment building, with some green space for recreation between them, we could probably fit the Earth's population into a space the size of Texas. We could leave the rest of the land for farming and just natural space for recreation and reforestation, allowing animals to live in peace.

What say you?

I currently live in a house, but if this was planned & designed right and there was adequate space for everyone, I'd be willing to do this.