Expert Voices 2025 | Access to Sustainable and Affordable Housing

The world has been grappling with a severe housing crisis for the past two decades. UN-Habitat estimates that by 2030, approximately 3 billion people will lack adequate housing. According to World Bank data, 1.8 billion people already live in inadequate housing today. Over the past 20 years, the number of people living in informal settlements has risen by 165 million, reaching 1.1 billion (UNDESA). This crisis, marked by unprecedented affordability gaps, is global in scope—even in the United States, one of the world’s strongest economies, there is a shortage of 7.3 million affordable housing units (NBER).

Addressing the global housing crisis requires bold actions paired with structural reforms.

One of the most cost-effective strategies is to reform development control policies, including zoning, land use regulations, and building codes, which have driven up housing prices and reduced the supply of affordable housing. These policies have increasingly priced people out of housing opportunities. Local and subnational governments can directly address housing affordability by reducing or overhauling certain development control rules to make more land, higher density, and diverse housing types available in accessible locations. For example, local governments can implement land banking to pool land resources and release affordable land parcels during supply shortages, helping to stabilize market fluctuations.

Inclusive development models, such as special-purpose zoning or the use of development rights incentives for affordable or social housing, can be found in the U.S., Europe, Latin America, and South Asia. For instance, Brazilian cities have used Zones of Special Social Interest (ZEIS) for over four decades. This mechanism allows flexible parameters for urban development, earmarking vacant or underutilized areas for affordable housing projects.

Another critical area is establishing more equitable housing finance systems. This involves improving access to financing for low-income households and affordable housing developers while reducing the cost of financing such developments. Many countries offer subsidies or incentives for affordable housing and low-income households. However, the structure of these subsidies is often skewed in favor of wealthier groups rather than those in need. National governments must reform subsidy policies to create a more equitable distribution system, shifting benefits towards low-income households and incentivizing affordable housing development.

And, of course, we cannot forget about 1.1 billion people living in informal settlements, highlighting the urgent need for systemic change. Rather than piecemeal slum upgrading efforts, we need to strategically collaborate with governments at all levels, the private sector, and communities to upgrade these settlements at scale. This should include simultaneously providing affordable housing linked to job opportunities, improved infrastructure, better public facilities and services, and access to public spaces—integrating informal settlements effectively into the urban fabric.

Housing must be realized as a fundamental human right. Solutions to deliver adequate and affordable housing should be both technically sound and people-centered, prioritizing the specific needs of marginalized and low-income populations.

In summary, addressing the global housing crisis demands policies directed at those most in need, structural reforms, and convergence between national financial systems and urban frameworks. These reforms should strengthen the construction industry and construction finance while promoting people- and nature-oriented urban planning. Local governments and communities play a strategic role in directing development to the "right" locations and people.
 

Anacláudia Rossbach is the Executive Director of UN-Habitat and an economist with over 20 years of experience in housing, informal settlements, and urban policies. She was previously the Director for Latin America and the Caribbean at the Lincoln Institute of Land Policy and served as Regional Manager for Cities Alliance, where she founded the Urban Housing Practitioners Hub. She also oversaw the development and implementation of Brazilian housing and slum-upgrading policies with the World Bank.