The Gem State Shines on Zoning Reform

Happy Tuesday, and welcome to another edition of Rent Free. This week’s newsletter covers the flood of housing reforms that passed the Idaho Legislature this session, and what they say about where the policy and politics of zoning reform is at.

While it doesn’t lend itself to easy alliteration like the “Montana Miracle,” Gem State lawmakers have now, like their eastern neighbors, passed a long series of bills right out of the YIMBY (“yes in my backyard”) playbook during a single session of the state Legislature.

Here’s what Idaho’s slew of zoning reforms says about YIMBY politics and policymaking in the states.

Top of the list is Idaho’s now-enacted “starter home” law, S.B. 1352, which would require cities of 10,000 people or more to update their land use laws to allow single-family homes on lots as small as 1,500 square feet within new subdivisions of at least four acres.

Minimum lot size laws can require new homes to sit on as much as an acre, or more, of land. Critics argue that these laws raise the price of housing by requiring each home to consume land in excess of what builders and homebuyers might want.

Over a dozen states have considered similar “starter home” reforms allowing small homes on small lots this year.

Idaho’s appears to be the most robust such policy to pass at the state level, given the small size of the lots and subdivisions it allows. Texas’ new starter home law, by comparison, caps minimum lot sizes at 3,000 square feet within new subdivisions of at least five acres.

Idaho additionally enacted another law, H.B. 800, that allows manufactured homes to be placed anywhere traditional site-built housing is allowed. This is another increasingly common reform that states are adopting to reduce the cost of housing.

Manufactured housing made up nearly a quarter of new homes built each year as late as the early 1970s. A mix of tightening federal regulatory standards, changing market conditions, and zoning regulations that prevented these homes from being placed in residential areas saw manufactured homes’ share of the market fall into single digits.

The pending housing legislation in Congress would loosen federal building code regulations on manufactured housing as well. Combined with local land use reforms like Idaho’s, that could see factory-built homes regain some of the former prominence they had as a source of affordable housing.

The state also enacted a law that overrides local zoning laws and homeowner association restrictions on accessory dwelling units (ADUs) in residential areas. By comparison, Montana’s ADU reforms overrode local zoning restrictions while explicitly preserving private covenant restrictions on accessory units.

Last on the list of the state’s reforms is its new law changing the state building code to allow apartment buildings of up to six stories to be built with a single staircase. Advocates argue this wonky reform will enable smaller apartment buildings to be built at lower cost and on smaller parcels of land, while not impeding fire safety (the initial reason for requiring two staircases in apartment buildings). The state building code change allows Idaho localities to pass their own ordinances allowing single-stair apartments.

A bill that would have allowed duplexes in single-family neighborhoods did not make it out of the Legislature after failing a committee hearing vote.

These reforms came out of the Legislature’s Interim Land Use and Housing Study Committee, which was convened last year to study the state’s land use regulations and make recommendations to increase housing supply.

This is similar to the process that led to the slew of zoning reforms now called the “Montana Miracle” that passed in 2023. The year prior, Republican Gov. Greg Gianforte convened a housing task force to make recommendations to increase housing supply for the Legislature to act on.

Indeed, there’s a lot about Idaho’s reform bills that is standardized. As mentioned, many states have passed, or are considering, liberalizing regulations around starter homes, single-stair apartments, manufactured housing, ADUs, etc.

Most localities’ zoning codes look similar and contribute to similar problems of high costs and less housing choice. Zoning reform advocates now have a pretty standardized set of legislative fixes they can roll out to address this standardized national problem.

The growth of off-the-shelf YIMBY reforms is likely one factor behind so many more housing bills being introduced, and passed, in state legislatures with each subsequent session.

“The vote count on all these bills was absolutely fascinating to me. There was no rhyme or reason,” says Hollie Conde, an Idaho-based fellow with the Sightline Institute who advocated for the housing reforms.

Conde notes that some lawmakers voted for ADUs but not for starter homes or duplexes. In the supermajority GOP-controlled Legislature, whether one was a more conservative Republican or a moderate Republican did not determine how they voted on the housing bills. The Legislature’s minority Democrats were also divided in how they voted on the bills, Conde says.

The one big determinant for how a lawmaker voted, says Conde, was whether they had been on the land use task force that studied the issue and recommended reforms. If they were task force members, then they voted for reform.

This scrambled partisan dynamic is not unique to Idaho. From Arizona to Texas to California, the intrapartisan splits on zoning reform are common, with Republicans and Democrats on either side of the issue. In almost every state, questions of whether to liberalize zoning restrictions do not have that strong of a partisan valence.

In the absence of partisanship, lawmakers on the left and the right can tell their own story for and against zoning reform. Conservatives can argue they’re supporting the free market by endorsing state zoning reforms. They can also claim to be sticking up for local control by voting against them.

Some Democrats argue that zoning reform is a progressive means of lowering housing costs, while others say it favors the interests of for-profit developers over community voices.

The lack of polarization on housing reform is, all things considered, probably a good thing for proponents of looser land use regulations. Even in very different state political contexts, similar sets of reform bills are getting passed into law.

The downside, of course, is that reformers can’t take any votes for granted. Any individual lawmaker could wind up anywhere on the issue.

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