Codes
The city and the county do not cite the same building codes
Published · every figure below was checked against its primary source on the date shown.
Two lists, one town
Fremont County publishes the codes it has adopted on its Building page. The City of St. Anthony prints its list on the back of its residential building permit application, in the paragraph that tells you what your construction documents must conform to.
They are not the same list. They are not close to the same list. And both apply inside the same town, depending on which side of a boundary your lot happens to sit.
| Fremont County (outside city limits) | City of St. Anthony (inside city limits) | |
|---|---|---|
| Building | 2018 International Building Code | International Building Code; International Existing Building Code |
| Residential | 2018 International Residential Code | Idaho Residential Code; IDAPA 07.03.01 Rules of Building Safety |
| Energy | 2018 International Energy Conservation Code | not named on the application |
| Electrical | not named on the Building page | 2017 NEC, with IDAPA 07.01.01–07.01.11 amendments |
| Mechanical / gas | not named on the Building page | 2012 IMC, 2012 IFGC, 2012 IRC |
| Plumbing | not named on the Building page | Idaho State Plumbing Code |
| Fire | not named on the Building page | 2015 edition, administered by the Idaho State Fire Marshal |
| Where to ask | 151 W 1st North · (208) 624-7200 | 420 N Bridge St Suite A · (208) 624-3494 |
Nothing in that table is inferred. Each column was transcribed from the issuing body's own current document on 14 August 2026 — the county's published Building page, and the city's application at revision 11.2023.
What the differences actually are
Three of them are worth naming, because they touch different trades.
- Residential. The county names the 2018 International Residential Code. The city names the Idaho Residential Code alongside IDAPA 07.03.01, the Rules of Building Safety. Those are different citations to different documents, not two names for one thing.
- Electrical. The city names the 2017 NEC with the IDAPA 07.01.01–07.01.11 amendments. The county's Building page names no electrical code at all — which does not mean none applies, since Idaho runs electrical licensing and inspection at state level, but it does mean the county page will not answer the question.
- Mechanical and gas. The city names 2012 editions: the International Mechanical Code, the International Fuel Gas Code and the International Residential Code, all 2012. Set against the county's 2018 residential code, that is a six-year spread on provisions your HVAC and gas subcontractors work to daily.
There is also a fire code on one side and not the other: the city names the 2015 edition, administered by the Idaho State Fire Marshal. The county's Building page does not name one.
How to read this without panicking
A newer edition is not automatically a better house, and an older edition is not a loophole. Code editions differ in particular provisions — a bracing table here, a ventilation calculation there — not in whether the result is safe to live in. Houses built to every one of these editions are standing all over this valley.
What the divergence actually costs you is precision. Your designer needs to know which list they are drawing to. Your mechanical contractor needs to know which edition their sizing comes from. And your plan reviewer will check against the list their own office enforces, not the one that was printed on a page you read.
The one email that settles it
Before plans are drawn, send the issuing office a single question and keep the reply in the project file:
“For a new single-family dwelling at [address / parcel number], please confirm which code editions your office is currently enforcing — building, residential, energy, electrical, mechanical, fuel gas, plumbing and fire.”
— the question worth asking in writing, because a code list printed on a form is evidence of what an office adopted, not proof of what it enforces today
Send it to whichever of these is yours:
- City of St. Anthony, 420 N Bridge Street Suite A, St. Anthony, ID 83445 — (208) 624-3494; inspections (208) 709-3030, 24 hours' notice
- Fremont County Building Department, Fremont County Courthouse, 151 W 1st North, St. Anthony, ID 83445 — (208) 624-7200
- Keep the answer. When a plan reviewer raises a comment eight weeks later, the dated reply is what tells you whether the comment is a change of position or a misunderstanding.
Why this page exists
No builder site in this valley publishes this comparison, and no out-of-area location page can — a page generated for forty towns does not know that this one has two permit desks with two code lists. It took reading both documents side by side, which takes half an hour and nobody does it because nobody has a reason to.
You have a reason to. It is your house.
Related reading on this site
- St. Anthony issues its own building permits — the sentence that decides which code list governs your build
- You build the sidewalk before you get the keys — the other requirement that exists on only one side of the line
- What it costs to build a custom home in St. Anthony — the fee differences that sit alongside the code differences
Common questions
Which building codes apply in St. Anthony, Idaho?
It depends which side of the city limits you are on. Fremont County's Building page names the 2018 International Residential Code, the 2018 International Building Code and the 2018 International Energy Conservation Code. The City of St. Anthony's own permit application names a different list, including the Idaho Residential Code, the 2017 NEC and three 2012-edition mechanical codes.
Why would the city and the county list different codes?
This site does not know, and will not invent a reason. Cities and counties adopt codes separately in Idaho and update on their own schedules, so lists drifting apart over time is ordinary. What is unusual is that both desks operate in the same town, so the divergence is visible to anyone who reads both documents.
Which list is the one I have to build to?
Whichever desk issues your permit. That is settled by the parcel, not by preference. Ask the issuing office to confirm its current adopted editions before plans are drawn — a code list printed on a form is a strong indication, not a substitute for asking.
Is the city's electrical code really from 2017?
That is what the city's application prints: Electrical Code, 2017 NEC, including amendments listed in IDAPA 07.01.01 through 07.01.11. Idaho amends the electrical code at state level, which is why the IDAPA reference sits alongside it.
Does an older mechanical code make my house worse?
Not automatically, and it is a mistake to read edition years as quality scores. Code editions differ in specific provisions, not in whether a house is safe. What matters practically is that your designer and your mechanical contractor know which edition they are working to, because that is what the inspector will check against.
Does the county name an electrical or plumbing code?
Not on its Building page. It names the three 2018 International codes. That is not the same as saying no electrical or plumbing rules apply — Idaho administers electrical and plumbing licensing and inspection at state level. It means the county's own page does not list them, so ask.
What is IDAPA 07.03.01?
It is the Idaho administrative rule known as the Rules of Building Safety, and the city's application names it directly in the list of documents your construction documents must conform to. It sits alongside the model codes rather than replacing them.
How do I avoid getting this wrong?
Ask one question, in writing, of the office that will issue your permit: which code editions are you currently enforcing? Put the answer in the project file. It takes one email and it is the cheapest insurance in the whole process.
Ask about a build in St. Anthony
Describe the parcel and roughly what you have in mind. What comes back is an honest read on which firms here take that kind of work, plus the one thing most people have not established yet: whether the city or the county will be reviewing your plans. Free, and nothing automated ever follows.
- Say where the ground is and what you intend to put on it.
- You are pointed toward the firms in this town with that work behind them.
- From there it is between you and them. No commission, no introduction fee, and nobody standing between you and your own contract.
One contact method is plenty — whichever you prefer. A human being writes back.