In the 60-80s, houses in Istanbul were built from sea sand and shells

The head of the oldest construction company "Ağaoğlu" Ali Aghaoglu spoke about the construction standards in the 60-80s, or rather about their absence: "Even when I was a child and my father was the head of the company, I saw what houses were being built from in Istanbul at that time. The main building material was concrete mixed with sea sand and shells. It was very difficult to get iron. To get at least one truck with iron, we had to wait for 6 months, and when we finally received it, it turned out to be of such poor quality that it broke at the slightest load. And this was the state of affairs for all companies. Therefore, 99% of the houses built in those years were built on this principle. I can say that the quality of such houses in Istanbul is much worse than those houses that were destroyed in the earthquake in Van.
In 2000, new quality standards were introduced, according to which they began to build reliable earthquake-resistant houses from the most durable monolithic structures." The program for the demolition of dilapidated housing, initiated by Istanbul Mayor Ekrem Imamoglu, will help solve the problem of the old housing stock of the metropolis.