The Hidden Rules Blocking Affordable Housing
It’s not the zoning map saying no. It’s everything else.

Affordable housing isn’t illegal in most cities, it’s just impossible.

You won’t find a big red “X” on the zoning map that says “no poor people allowed.” In fact, many cities have taken steps to allow more housing types, loosen zoning restrictions, and support affordability goals. But here’s the catch: once a project enters the review process, it quietly dies via a slow bleed of hidden restrictions, technical standards, and conflicting code requirements.

In today's article, we're going to break down the lesser-known rules that quietly stop affordable housing. They're not neccesarily hard “no,”s they're more like thousand of little “not like that.”s

Minimum Lot Sizes

‍Sounds boring but is actually devastating. Minimum lot size requirements lock neighborhoods into a format where only large, expensive homes make sense and smaller, more affordable options are zoned out of existence. Even if your zoning technically allows a duplex, requiring 7,500 square feet per unit turns it into a theoretical option rather than a real one. It’s not just duplexes, either. Cottage clusters, fourplexes, ADUs, and missing middle housing of all kinds get disqualified on lot size alone. These requirements also reinforce outdated notions of what a “normal” lot looks like, based more on post-war suburban ideals than current housing needs. It’s exclusion through arithmetic. Square-footage mandates  pretend to be about neighborhood character but functionally block affordability, flexibility, and growth.

Parking Minimums

‍Requiring 1.5–2 parking spaces per unit makes affordable housing significantly harder to build, especially on small lots, narrow parcels, or sites near transit. Parking isn’t free. It adds substantial cost in terms of land, construction, and design complexity. Developers either eat the cost, which cuts into feasibility, or pass it on, which drives up rents and sale prices. Either way, it pushes out smaller-scale or nonprofit housing builders who operate with tight budgets and limited margins. Parking minimums are also wildly out of sync with how people live. Especially in urban areas with walkability or transit options. Forcing every unit to come with a parking spot assumes car ownership is universal, which it isn’t. And when you think about it: if your policy says “build near transit” but still demands suburban parking ratios, your policy is just pretending to be planning.

Height Restrictions and FAR Caps

‍You can legalize multifamily all you want, but if you cap height at 30 feet and slap on a restrictive floor area ratio (FAR), you’ve quietly made density illegal again. These caps sound like neutral planning tools, but they’re often used to protect sightlines and shadows at the expense of livability and supply. Form is policy, and in this case, it’s exclusionary policy.

Occupancy Limits and Unit Caps

‍Many cities restrict how many unrelated people can live in a single unit. These policies, often framed as “health and safety”, make shared housing and co-living arrangements illegal. Combine that with unit-per-acre limits, and even in zones that say they allow multifamily, you end up with one-bedroom apartments spaced out like luxury condos. It’s anti-density in disguise.

Design Standards Masquerading as Character Protection

‍Façade modulation. Roof pitch angles. Material requirements. Setback averaging. These things matter...but not all at once, and not at the cost of affordability. Many codes load up small projects with so many design standards that only the biggest developers can comply. The rest walk away. “Character” becomes the velvet glove on the iron fist of exclusion.

The Paperwork Gauntlet

‍Even by-right projects often face unclear workflows. This translates into slow review timelines and multiple rounds of revision. If it takes 12 months and 6 resubmittals to build a fourplex, that’s more of a filter than a process. And the things getting filtered out are usually smaller projects, missing middle typologies, and naturally affordable housing. Bureaucracy doesn’t need to say no; it just needs to say “not yet”...until you run out of money.

Conclusion: Death by a Thousand Cuts

‍Affordable housing doesn’t get killed by one big bad policy. It gets worn down by dozens of small, invisible ones. A city can say “we support housing” while simultaneously making it unbuildable. If you want to fix the housing crisis, don’t just look at what’s allowed, look at what’s actually feasible.

Because if your code says it allows affordable housing, but no one’s building it, your code is a liar.

Up Next: Is Zoning Really Neutral?