Expert: Cary Simmons - 6/4/2010

Question
Suppose a 100 storey building is erected today. now for how many years would it last? Or after how many years it has to be demolished to erect a new one?

Answer
Neelesh:

In the US, and perhaps all parts of the world where the local economy can justify a building of the size your question concerns, the life-expectancy is usually dictated by economics.  In most cases several issues converge to determine when the building is no longer economic to stand.  Among them, the most important are generally to cost to maintain, the value of the underlying site for a larger building or other uses, the decline of the neighborhood and thus the marketability of space within the building, and the amortization rate of the initial construction financing.  There are exceptions, such as prominent headquarters structures (Hong Kong Bank), signature or landmark structures (Seagram Building in NYC) and successful adaptive reuse (Chicago Merchandise Mart), but these pleasant surprises are not factored into the original financing.

If your question is driven more by curiosity regarding the life-expectancy of materials, privately-financed high-rise buildings built since the 1960's are generally assumed to reach obsolesce in less than fifty years, sometimes as few as twenty years and the materials are chosen accordingly.  Most publicly-financed buildings and religious structures are expected to last indefinitely and are constructed of more permanent materials, but these buildings rarely reach sizes comparable to your example.

I hope this helps.