How we build these pages

Where the data comes from

Three sources, in this order:

1. The city's code of ordinances. Published by Municode, the codifier most US cities use. We read the sections a city writes itself — the permit chapter, the exemption list, the fee schedule.
2. The state building code, where the state has one. Florida and Tennessee set a statewide baseline that applies in every city; a city can tighten or loosen it, but if it stays silent, the state rule governs. Texas and Arizona impose no statewide residential code, so each city adopts its own edition of the International Residential Code.
3. The building department's own site, for the things codes rarely carry: current fees, review times, and the link to apply online.

City boundaries, population and coordinates come from the US Census Bureau. Those are public-domain files, not estimates of ours.

Why the answer isn't in one sentence

This is the part most permit articles skip. Whether you need a permit is almost never written plainly in one place. It's assembled from three layers:

The city adopts a model code by reference — usually the International Residential Code. That code contains a section, R105.2, listing work that needs no permit. Then the city amends that list by ordinance. Then separate zoning sections set height and setback limits, which are a different question entirely.

That last distinction matters. “No fence over six feet may be built” is a height limit, not a permit trigger. Reading it as one produces a confident, wrong answer. We treat zoning limits as context for the threshold and never as the permit rule itself.

How each answer is checked

Every extracted rule carries a confidence score. Below 0.85, the page does not print an answer at all — it shows the ordinance section and the department's phone number instead, and says plainly that we couldn't confirm it.

That threshold is deliberate. On a page about permits, a confident wrong answer costs a reader real money and real rework. An honest “we couldn't confirm this” costs them one phone call.

Before an answer is published it also has to pass a validator: the section it cites must be one actually present in the source we read, the values must be in range, and anything below the confidence threshold must carry a written reason. Answers failing any of those are rejected rather than softened.

Right now the site covers 101 cities with 1,253 published answers; 73% clear the confidence threshold and the rest are shown in the honest fallback form.

What this method can't see

A code of ordinances describes the city's general rule. It does not know about your particular lot. These pages will not catch:

• an HOA that is stricter than the city;
• a historic district or overlay with its own review;
• a floodplain designation, which in many cities cancels the normal exemptions;
• an easement crossing your yard;
• a fee that changed after our last check.

That's why every page carries the date it was checked and a link to the section it came from. Treat this site as the fast first answer, and the department as the final one.

How often it updates

Codes are re-published by the codifier on their own schedule — some cities several times a year, some once. We record the publication date of the code we read, and that date is what appears on each page as “Checked”. It is the real date of the source, not the date the page was generated.

Found something wrong?

Tell us and we'll fix it, and say on the page when we did. The most useful report names the city, the project, and the ordinance section you think we misread — that's enough to verify in a few minutes.

Contact form goes here before launch.