In their ongoing bid to bring down housing costs, statehouse Democrats this year have shifted their attention from townhomes and apartments to pursue a new strategy: shrinking the single-family home.
The Colorado House earlier this year passed two bills designed to make it easier to build detached single-family homes on smaller lots. The legislation comes in response to what housing advocates say is an underappreciated factor in the state’s housing crisis — the homes we build today are simply a lot bigger than they were decades ago.
That means more land and more construction materials, at a time when the costs of both are skyrocketing.
If passed by the Senate and signed into law, House Bill 1308 would require many local governments to allow residential property owners to split their lots in two, allowing two single-family homes to be built there instead of one.
House Bill 1114, meanwhile, would ban most cities from requiring lots larger than 2,000 square feet to build a house. That would slash lot size requirements by more than two-thirds in many neighborhoods.
Both bills passed by a wide margin, with a handful of Democrats joining House Republicans in opposition. They are scheduled for Senate committee hearings April 23.
The measures are an extension of the state’s recent efforts under Gov. Jared Polis to increase housing density in communities across the state. Studies show that upzoning — the practice of changing local zoning rules to allow denser housing types — leads to more homes, which in turn, should help drive down costs in a state that faces a shortage of more than 100,000 units.
But while most of the legislature’s efforts have focused on allowing apartments and “missing middle” units like duplexes, townhomes and condominiums, lawmakers now say cities need less expensive single-family homes, too — in part because that’s still the only thing you can build on most of Colorado’s residential land.
“If (communities are) going to insist upon single-family-only use, then we need to tackle affordability in a different way,” said Rep. Rebekah Stewart, a Lakewood Democrat who is cosponsoring the bill to shrink lot sizes. “In Lakewood now, the smallest lot that you can build a single-family home on is 6,000 square feet — that’s the smallest, the very very smallest.
“No one’s going to be able to afford a starter home on a 6,000-square-foot lot.”
The proposals come at a time when local governments are already revamping their zoning codes to allow more housing. Recent state laws have required local agencies to zone for more density near transit, relax parking requirements in neighborhoods and allow homeowners to build accessory dwelling units in their backyards. Some cities have gone even further than state law requires, even as many local residents push back against efforts to add housing.
Earlier this month, Lakewood voters repealed four new zoning ordinances that allowed duplexes and multiplexes in many of the city’s suburban neighborhoods. The zoning overhaul, which had taken effect Jan. 1, also imposed a maximum lot size for new single-family homes — 5,000 square feet.
But far from deterring lawmakers, some said the local opposition only reinforced the need for the state to step in.
“If local control was the solution, we should have found it by now,” said state Rep. Andrew Boesenecker, a Fort Collins Democrat, who is cosponsoring the lot-splitting measure. “Unfortunately, what happens is, year after year, this problem gets worse.”
A push toward smaller homes
A recent project in Denver shows how lot splitting can lead to more affordable housing.
The city gave Habitat for Humanity of Metro Denver a 9,200-square-foot residential lot in the Villa Park neighborhood. Nearby homes on a lot that size can sell for upwards of $700,000, according to Zillow. So instead, Habitat worked with the city to split the land in half, building two homes that appraised for far less — $490,000 and $558,000 at the time they were sold in 2024.
(Habitat, a nonprofit builder, sold them for even less to keep them affordable for low-income buyers.)
At a press conference earlier this month, Kory Whitaker, Habitat’s vice president of housing programs, said the organization has built over 20 homes in Denver recently through split lot projects like this one, with over a dozen more in the works.
But such projects aren’t easy to do. It can take a long time to get the approvals needed and to secure new titles for the separate lots, delaying construction and driving up development costs. Sometimes, projects don’t happen at all due to opposition from local residents or city officials.
Under the bill, local governments would have to create a streamlined administrative process to approve splitting a residential lot into two, as long as the resulting properties are at least 1,200 square feet each.
The logic behind the push to reduce minimum lot sizes is similar. Land costs doubled over the last decade, according to the Colorado Futures Center, comprising nearly 20% of the total cost of the average house. So the smaller the home, the more affordable it can be.
But Colorado’s zoning codes encourage just the opposite. A recent National Zoning Atlas study found that Colorado has some of the largest residential lot size requirements in the country, with many Front Range neighborhoods prohibiting homes from being built on lots smaller than 7,000 square feet.
According to Housing Forward Colorado, an initiative led by the Southwest Energy Efficiency Project, the average redevelopment project in Denver in 2024 replaced a 1,299-square-foot home with a 4,405-square-foot home. Most of those new homes sold for over $1.4 million.
If passed into law, the proposal wouldn’t prevent large homes from being built, but it would allow smaller ones than most residential zoning districts currently do.
Neither bill is likely to be a silver bullet, says Matt Frommer, a policy manager at SWEEP.
Similar efforts in other states have led to dozens or hundreds of new homes a year, a far cry from the volume of housing the state needs. But, there’s growing evidence that they do help.
“It’s a long-game strategy,” Frommer said. “It’s a trickle of new housing” as older homes are replaced.
Local pushback
At the local level, cities have met the state’s density push with a range of responses, from enthusiastic adoption to reluctant compliance or even outright defiance in the form of lawsuits.
In a repeat of past zoning fights, the Colorado Municipal League has criticized the legislation because it takes away local control of neighborhood development.
“Land use decisions shape neighborhoods for generations, affecting infrastructure, traffic, water demand, public safety, and, of course, neighborhood character,” Bev Stables, a lobbyist for the group, said at a committee hearing in March. “An administrative process that bypasses public hearings effectively silences residents and neighbors, eroding trust in local government, and diminishing transparency.
“Coloradans expect and deserve a voice in decisions that directly impact where they live,” she said.
But only a handful of city officials testified against the bills in committee, a stark contrast from the widespread local pushback to state zoning bills in prior years.
Instead, a new divide has emerged in recent months — not between local governments and the state, but between local voters and those they’ve elected to office.
In Littleton, for instance, voters in November reelected the city’s mayor and a slate of City Council candidates who support greater density. But they also approved a city charter amendment blocking the council’s efforts to legalize duplexes and other denser housing types within single family neighborhoods.
In Lakewood, a similar dynamic played out this year, when voters repealed the pro-density zoning changes approved by the City Council, following a divisive campaign. Opponents of the new zoning rules claimed without evidence that the city wanted to “bulldoze” its single-family neighborhoods on behalf of private developers and force residents into “permanent rentership.”
That pattern has played out time and again in communities across the state. Polling consistently shows that Coloradans want more affordable housing, but when push comes to shove, they often reject efforts to build it in their own neighborhoods.
“I think what frustrates me is when it seems like fear and misinformation is used as a tactic,” said Stewart, a former Lakewood council member. “We know that the facts and the evidence point towards the types of steps we need to take in order to increase housing availability, first-time homeownership and affordability. But if someone is afraid that their home is going to get bulldozed, it’s just very, very difficult to have a real conversation.”
The antidensity campaign prevailed with about 65% of the vote in a low-turnout April 7 election.