The 21st Century Road to Housing Act, which passed both chambers of Congress by a huge margin, is designed to bring relief to Americans struggling with lofty prices and mortgage rates. Its impact might not be felt for years, however, given the often long timelines on construction projects and state and local statutes that limit development.

The fate of the legislation had been up in the air after President Donald Trump announced that he wouldn’t sign the measure. Trump ultimately opted not to use his veto power to try to block the bill, clearing the way for it to become law.

Here’s what to know about the new law and how it could change the housing market. 

What’s included in the housing bill?

The bipartisan legislation aims to alleviate a housing shortage that has contributed to voters’ frustrations over affordability. The law includes new rules making it easier to develop factory-built housing and encouraging localities to remove barriers to construction.

The housing act also seeks to curb large investors’ footprint in the housing market, in part by barring institutional investors that own more than 350 homes from purchasing additional single-family properties.

Among the law’s initiatives is a program to incentivize state and local governments to overhaul restrictive zoning policies that constrain housing construction. There are provisions to establish pre-approved home designs and streamline environmental reviews in an effort to reduce the regulatory hurdles that slow or block new construction. In addition, the bill would create a pilot program to give competitive federal grants to localities that convert underused commercial buildings into affordable housing. 

The legislation also includes nine provisions relaxing regulatory requirements for community banks that could make it easier for them to extend mortgage loans. 

Read more: Trump Undercuts GOP Message With Snub of Housing Bill

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How did President Trump react to the bill?

After signaling that he would sign the housing bill once Congress approved it, Trump abruptly declared that he wouldn’t put his signature on the measure unless Congress adopted an unrelated voter ID bill. The move provided a dramatic last-minute twist to lawmakers’ efforts to adopt the bill. 

Trump could have vetoed the legislation outright, potentially leading Congress to vote on whether to override the veto. But by neither signing nor vetoing the legislation, it automatically became law 10 days after being formally sent to the president’s desk. The legislation originally passed the House of Representatives and the Senate by overwhelming majorities.

How many new housing units does the US need?

Estimates vary. Freddie Mac in November 2024 said the US was 3.7 million housing units short of what was needed based on demand from a growing population. The National Association of Realtors in June 2021 estimated the shortage to be 5.5 million units, based on building trends over the previous 20 years compared with construction rates from 1968-2000. 

The White House in the spring said that the shortage runs to at least 10 million single-family homes.

How did the US get into this situation?

The high cost of housing today is largely due to a supply shortfall 20 years in the making. Homebuilding cratered in the wake of the 2008 financial crisis and still hasn’t returned to pre-crisis levels.

Even as construction slowed, costs shot up during the Covid-19 pandemic as people sought more comfortable living situations. Population growth fueled more demand in many cities. Home prices have remained high even as mortgage rates more than doubled in recent years. 

Does the federal government have much influence over the housing market?

The government-controlled mortgage companies Fannie Mae and Freddie Mac underpin the mortgage market by pooling loans into securities they sell to investors, which frees up mortgage originators to make additional loans. 

But the federal government’s ability to influence prices and construction activity is limited: Many of the factors driving up costs — including restrictive zoning, expensive permitting processes and complex regulations — are determined at the state and local levels. 

Could restrictions on institutional investors’ ownership of single-family homes affect supply?

It isn’t clear how much of an impact the investor limits will have on housing prices. Larger institutional investors own only about 2% of the nation’s single-family rental housing stock. 

The measure could deter investment in the market. But House lawmakers successfully stripped a controversial provision requiring large investors to dispose of homes built as rentals within seven years. Housing experts and advocates said such a requirement would limit one of the few existing sources of new supply and could jeopardize construction of up to 100,000 new homes per year. 

What role does zoning play?

Zoning plays a big role, in some cases making it prohibitively expensive to build affordable housing because it restricts the type and size of homes in many areas. Many communities dominated by single-family homes have zoning rules limiting the construction of apartment buildings, for example. Regulatory costs at all levels — state, local and federal — accounted for 26.4% of the average sales price of a house as of January, according to the National Association of Home Builders.