Colorado Gov. Jared Polis signed two marquee land-use reform bills into law Monday, clearing the way for the building of more accessory-dwelling units and denser development in cities and suburbs across the Front Range.

“The success of this bill will be measured in years,” Rep. Steven Woodrow, a Denver Democrat who sponsored the density measure, said at the signing ceremony outside a light rail station in Denver. “1.7 million more people are projected to move to Colorado by 2050.

“And this bill says: ‘Yes, we will have a space for you. Yes, you coming here will not make it less affordable for everyone else. Yes, Colorado is open.’ ”

In all, six land-use reform bills passed the legislature before it adjourned last week. Polis in recent days signed three of them into law — measures dealing with minimum parking requirements, density goals near transit and accessory-dwelling units. (A fourth, a ban on local occupancy limits that aren’t safety related, was signed earlier this spring.)

The bills underwent various changes on their (at times fraught) paths through the legislature, and the most sweeping provisions apply only to certain parts of Colorado — largely cities along the Front Range.

Here’s a look at what each will do, where they apply and how they’re expected to affect the state.

Wait, first — what’s the goal here?

The point of these reforms is to loosen local land-use and zoning rules and allow for more development, ultimately increasing the state’s supply of housing and, hopefully, making it more affordable.

That may mean allowing homeowners to build carriage houses by-right (for rental purposes or so that a relative can move in). Or it might mean developers of affordable projects can build more units because they don’t need to factor in parking requirements. It also will mean denser development near transit-rich areas because, supporters argue, that maximizes space, increases supply, bolsters use of public transit and reduces resource-sucking sprawl.

Think of it this way: Land-use reformers long have groused that local resistance makes it harder to bolster density or allow for different types of housing, particularly in neighborhoods where residents are accustomed to single-family homes. (Fort Collins is a prime example.) But these new reforms generally should leapfrog the ability of local residents (or city officials themselves) to block development at the municipal level, and they will clear the way for more types of housing.

Parking minimums

Municipalities across Colorado have varying sets of requirements around how many parking spots are required for various types of developments — apartment buildings, bars, restaurants, movie theaters. House Bill 1304, sponsored by Democratic Reps. Stephanie Vigil and Woodrow and Sens. Nick Hinrichsen and Kevin Priola, generally eliminates those requirements for residential developments near transit stops in Front Range cities.

Initially, the bill was more sweeping and would’ve entirely nixed the requirements in those cities. But it was amended in the Senate, paring it back to just areas within certain distances of stations and stops along major transit routes.

The new law also gives local governments the ability to require one spot per housing unit if they determine certain new developments would have a “substantial negative impact” on the surrounding area without parking.

The requirements go into full effect June 30, 2025.

Accessory dwelling units

Accessory-dwelling units — otherwise known as ADUs, garage apartments, carriage houses or casitas — are allowed to varying degrees in cities across Colorado. House Bill 1152 generally requires local governments along the Front Range to allow for homeowners to build an ADU on their property, with local approval only to ensure they meet certain administrative and size requirements.

Basically, affected cities can no longer say no to ADU construction or institute requirements that effectively ban them. The law also includes $5 million in grant funding to help middle and lower-income households build ADUs or to help subsidize ADUs that will be rented to tenants at lower income levels, plus millions of dollars more for loan or down-payment assistance.

The bill was sponsored by Reps. Judy Amabile, a Boulder Democrat, and Ron Weinberg, a Loveland Republican, plus Democratic Sens. Kyle Mullica and Tony Exum.

Affected local governments are required to comply by June 30, 2025.

Density near transit

House Bill 1313 was appropriately the densest housing policy passed this session. It, too, applies only in certain areas — roughly 30 cities and suburbs along the Front Range.

Under the law, affected local governments will have to come up with a density goal for areas near stops on major transit lines, including zoning for an average 40 housing units per acre. Cities will then have to come up with plans to hit that goal and then provide updates to the state on their progress.

The state has put forward $65 million in grants and tax credits to help bolster subsidized housing and infrastructure near those transit spots.

Effectively, the law seeks to incentivize — then require — denser building in certain areas. Here’s an example from the state: If a city has 100 acres of land within the required proximity of transit, then that city must allow a zoning capacity of 4,000 housing units in those areas. That doesn’t mean that the city must have 4,000 new housing units; in fact, the law won’t penalize local governments if they’ve fully complied with plans but development hasn’t followed.

In addition to Woodrow, the law was sponsored by Democrats Rep. Iman Jodeh and Sens. Winter and Chris Hansen.

Weren’t there concerns about gentrification?

Yes, plenty.

Housing advocates and progressive lawmakers expressed concern that current residents would be forced out of areas that would suddenly become more valuable for development. To blunt that concern, the density law requires local governments to include several strategies in their plans to avert displacement and ensure affordability. Those strategies can include regulating short-term rentals, supporting and incentivizing subsidized housing, or requiring inclusionary zoning ordinances, like Denver’s.

Implementing those strategies is now required under state law and must be part of the density plans.

How much housing will be built? How soon?

That’s slightly tricky. The parking and ADU laws will theoretically spur more development by lifting requirements that have limited building (and, in the ADU bill’s case, by offering some money to help homeowners).

Now, the density bill does require local governments to zone certain areas for denser development. That doesn’t mean that Denver will have an average of 40 units per acre near transit stops. It just means that the city (and other affected Front Range municipalities) must allow, via zoning rules, for that level of development to take place.

But the law doesn’t require Denver or Boulder or Thornton to stand up a couple of apartment high-rises on their own. That’s up to developers. The cities just have to clear a path.

As for the timeline: As Woodrow said, the impacts — success or failure — of these reforms will take years to bear fruit. Development doesn’t begin overnight. The density measure will take the longest to implement, since local governments won’t have to submit reports with their density goals until New Year’s Eve 2027.

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