A growing group of cities has found a way to clear a building permit in days instead of months. The trick is to do the hard review once, in advance, and let every project that fits inherit it. New research from the Pew Charitable Trusts finds preapproved building plans are cutting timelines in half and shaving thousands off the cost of a home. Here is how they work, and where the model runs out of road.
A preapproved (or permit-ready) plan is a complete house or small-multifamily design that a city has already reviewed and cleared against its zoning and building code. A builder selects it off the shelf, fits it to a lot, and moves almost straight to a permit. It is the same logic as TSA PreCheck: the scrutiny happens once, up front, and everyone who clears it skips the line afterward.
Key takeaways
- A preapproved building plan is a design a city has already vetted against its code, so a builder can skip most design and discretionary review and get a permit in days.
- Programs report roughly 2x faster pre-construction: Seattle cut ADU permits from 160 days to 54; Claremore issues pre-cleared permits in 24 to 48 hours.
- Savings run about 1 to 2% of development cost, commonly $5,000 to $10,000 per home and up to $35,000 in Tulsa.
- It is already producing homes: preapproved designs account for 7 to 20% of new units in cities that have adopted them.
- The catch: preapproved plans only fit standard, simple projects. For everything else, the real lever is whether a plan is complete and code-conformant on the first pass.
The idea: review once, build many
Every new home runs a gauntlet before construction starts: a custom design, financing, discretionary boards, and a full code review. Most of that work is repeated from scratch on every single project, even when the homes are nearly identical. A preapproved plan breaks the loop. A city reviews a complete design once, confirms it meets zoning and building code, and publishes it. After that, any builder can pick it up and move almost straight to a permit. The payoff shows up before a shovel ever hits the ground.
Days, not months
The clearest result is speed. Because the heavy review is already done, a participating builder submits a known-good plan and the city can issue quickly. The reported reductions are not marginal: Seattle's detached-ADU permit time fell from about 160 days to 54, a measured before-and-after, and smaller programs from Oklahoma to Florida report cutting weeks to months off every home.
Cheaper to design, cheaper to carry
Speed is also money. A preapproved plan saves the design fee, trims the cost of capital by shortening the timeline, and reduces the carry cost of a project sitting idle in review. The savings land at roughly one to two percent of total development cost, and they scale with the size of the build.
Every month a project waits in review adds roughly 1% to its cost. Speed is not a convenience. It is the price of the home.
It is already building homes
This is not a thought experiment. In the cities that have adopted preapproved plans, the designs are responsible for a real and rising share of what gets built, especially the smaller, more affordable formats the housing shortage needs most: starter homes, ADUs, and missing-middle units. In Hawaii County, Jackson, and South Bend, preapproved designs already account for a meaningful slice of new production.
From pilot to statewide
What began as a handful of city pilots is becoming state policy. Several states have moved to create or fund libraries of preapproved designs that any local government can adopt, which solves the hardest part for small towns: the up-front cost of vetting the plans in the first place. California, Colorado, Arizona, Oregon, and Maine have enacted statewide action, three of them in 2025, with Connecticut, New York, Pennsylvania, Tennessee, Vermont, Washington, and Hawaii in development.
Enacted statewide action · 5 states
Bills introduced or programs in development · 7+ states
A federal bill would fund a national library of preapproved designs. Three of the five state laws passed in 2025 alone, and the policy is moving from pilot to mainstream fast.
The limit of the model
Preapproved plans are a genuine win, but they solve a deliberately narrow problem. By definition, a stock plan only helps a project that fits the stock plan. That covers single-family homes, ADUs, and simple small-multifamily on straightforward lots. It does not cover the custom home, the awkward infill site, the renovation, or the larger and commercial projects that make up the bulk of what a permitting office actually processes.
So the deeper lesson of the preapproved-plan movement is not really about stock designs. It is about where the review happens. These programs work because they move the hard, code-checking work to the front, before submittal, so that by the time a plan reaches the counter it is already known to conform. That is the actual mechanism, and it is the same one behind the fastest jurisdictions in our city and county performance analysis and the statutory clocks in our 50-state regime map. The stock plan is just one way to get there.
The first-pass guarantee, for every plan, not just the stock ones.
Preapproved plans prove the thesis: front-load the code review and the permit clears in days. Permavia does that for the other 99% of projects. We interpret your plan set, cross-check it against the local code, and surface the exact changes needed for first-pass approval, so any plan arrives at the counter already conformant.
explore PermaviaThat front-loading is exactly what an intake completeness check and a pre-submittal permit review do for any plan set, not just the stock ones. Browse the permit guide directory to see how your jurisdiction reviews, and what it takes to clear on the first pass.