Iran needs to build one million new housing units per year to keep pace with demographic trends, such as marriage, according to the Statistical Center of Iran. But the bigger issue for aspiring low- and middle-income homeowners is the type of housing being built in Tehran, where real estate developers have shown a preference for high-end construction aimed at the more affluent. “The units built over recent years do not match the demand of the buyers in terms of size and location,” said Mehdi Ravanshadnia, an associate professor of construction at the Islamic Azad University.