Recently a New York Times headline and story asked the question, “Would the Housing Crisis Ease if Boomers Rented Out Their Empty Rooms?” My immediate answer was, “No, of course not.” I’ve heard versions of this idea for more than a decade, but I think it’s worth walking through the article and looking at why the idea is so persistent, why it won’t “ease the crisis,” and how we might change things so that the idea might catch on and scale to put a dent in the problem of lagging supply that creates the scarcity that drives up prices and hurts people with less money to spend on housing.

The story leads with Monte Anderson, a Dallas area developer who purchased an abandoned 2,400 square foot home and converted it into a four-unit building. Anderson calls it “the roommate house” and “a suburban retrofit.” He spent $1 million to bring the project to life and rents to a variety to demographics at $1,800 a month. The article doesn’t cover financing of the building or operating costs. Given his stated costs, and relatively low rents, it’s hard to understand how Mr. Anderson is getting a return on his investment, especially if he borrowed money. He seems to have built the project to make a point and maybe test the concept—he lives in it too.

The article points out that, “It takes money to buy land, time to secure permits. In the meantime, construction costs have exploded. That’s why most new homes tend to be luxury rentals or higher-cost houses, rather than something a person with a middle or lower income can afford. Those lower-cost units, however, are the ones in the shortest supply.”

This is true, and seems born out, ironically maybe, by Mr. Anderson’s example. His development costs, $250,0000 per unit, isn’t exactly cheap and we don’t know how much he paid for the land. In another example in the article, a different developer explains he bought an old bombed out house for $300,000, spent $1 million, and is renting them for roughly the same as Mr. Anderson. The article acknowledges that claims “he lives in a single-family home, in accordance with local zoning codes, when in reality the home contains four apartments in a country that needs more of them.” According to the Times, there are 145 million single-family homes and by implication, suggests that there are at least 145 million opportunities to duplicate Mr. Anderson’s experiment.

I’d like for this to be true, that we could simply take three-bedroom homes that are currently inhabited, create a platform or model that would allow the rental of those two extra rooms at scale. When looking at the numbers of single-family homes, it appears to be a fallow field only waiting for a plow and a patient farmer. Here’s why it won’t ease the crisis in any meaningful way.

Have you ever tried to get a permit from your city or local jurisdiction for anything? More than 10 years ago, I fought to preserve microhousing in Seattle. It was a model that exploited a “loop hole” in the code that allowed five separate people to live in a single unit. It meant that smaller, multifamily lots could be developed with small rooms attached to a shared kitchen. It was legal until it wasn’t. New rules were created that made it impossible. We tried to simply regulate the idea, but that wasn’t good enough. Angry neighbors argued the units were too small, inhumane, and too expensive. They were abolished. And what happens when Mr. Anderson has one of his “roommates” stops paying rent or behaving in a threatening way? Will local rules let him evict the person efficiently without wreaking havoc on his existing tenants? The very reasons that the Times articles cites for conventional housing being expensive is why this solution could be very hard to scale up.

Both examples highlighted in the Times had redevelopment costs of $1 million. Where is financing going to come from for such a risky endeavor? The answer is the money is not going to flow to these projects. Lending markets are lending at high prices and they are not big risk takers. Private capital could ease this, but where’s the return? If prices are high, more investment makes sense. But that means higher rents. And if regulatory hassles on parking and other requirements and time and costs, these solutions, as amenable as they might be, simply won’t be affordable. Government would have to not only not regulate these arrangements while they work themselves out, but they would likely also have to offset the risk by offering cheap loans or direct grants, something that is not in the playbook most housing agencies and local governments.

One of the biggest problems with long term, 30-year mortgages is that they depend on inflation which is created by scarcity. Neighbors won’t come right out and say it, but usually, they have a strong intuition, mostly false, the housing around the corner corrodes their equity or the market value of their house. Parking concerns, worries about noise and too many people using local amenities tend to be persuasive to local officials who ultimately issue permits. If the idea of converting single-family homes to multifamily homes catches on, like microhousing in Seattle, it might be short lived.

End zoning as we know it in favor of building codes which emphasize health and safety not location and use and we could see big benefits in reduced housing costs. End the mortgage as we know it and these solutions will proliferate. Abolishing the regulatory barrier between a person who needs housing and one who has it, zoning, would provoke much innovation. And if tenant landlord law was treated as contract law, not a social justice issue, similar innovation would be supported. The mortgage as a tool favors scarcity and means existing homeowners will be skeptical of change, including subdividing existing homes. My answer to the questions in the Times headline and story is still, “No,” but there is a pathway toward vacant rooms as part of the solution.