Transwikied from- http://lifeafterpeople.wikia.com/wiki/Tone_HQ
Tone HQ is a 27 floor, 101.25 m building that houses Tone Corporation (not real) and the building is also not real. But, will it last without anyone?
1 day after people: The lights of most building in New York have failed, but Tone HQ's lights flicker. Eventually, they, too, will fail.
2 days after people: Tone HQ's lights use so much power from flickering that they fail. Ricoh sign in Manhattan remains a light.
1 year after people: Tone HQ starts to be covered in plant life.
4 years after people: The Ricoh sign becomes dark as the light bulbs burn out, leaving Spring Preserve Visitor Center for a few more years the only building to have powered lights.
50 years after people: The windows broke from the fire, plantlife is now growing freakishly fast. The top of the tower has rusted.
100 years after people: Rust has now covered the whole building. The roof falls.
200 years after people: Tone HQ is on the brink of collapse, most buildings have collapsed.
300 years after people: One World Trade Center destroys the Tone HQ, leaving only the bottom.
1000 years after people: The bottom 8 floors collapse due to more rusting.
10,000 years after people: The site is now flooded.