FireApproved
On this page
  1. Why it matters
  2. How it works
  3. The paths
  4. What people mix up
  5. How to check
  6. Limits
  7. Related records

Home / Guides / How the documents differ / Idaho WUI code status

Idaho WUI code status

Last verified 2026-08-26.

This page is Idaho law.

Idaho does not have a statewide IWUIC construction book. Idaho Code 39-4109 adopts the International Building Code, the Idaho residential code, the energy code, and the International Existing Building Code. IWUIC is not on that list.

You are looking at a lot in Idaho and asking which book binds a new roof. The statewide path is ordinary IBC or IRC construction unless a city or county adopted a WUI overlay. This site does not invent that overlay.

Why it matters

Embers still reach a deck in McCall or the Boise Foothills. A missing statewide WUI book means you cannot spec “Idaho IWUIC Class A” as a state minimum. You can spec a local ordinance if one exists, or an insurer checklist such as IBHS Wildfire Prepared. See the hardening ladder.

How it works

39-4116 tells local governments that issue building permits to adopt, by ordinance, the IBC, the Idaho residential code (parts I–III and IX), and the 2018 Idaho energy conservation code, with the board’s amendments. The same section says locals are not required to adopt the other referenced codes in the IBC.

That is the statewide picture. A city may still adopt IWUIC as a local overlay. Eagle City Code 7-1G-3 (Ord. 947) adopts the 2018 IWUIC, including Appendices A and B, inside a mapped overlay district. A city-approved fire-protection plan can exempt a project from that article, and the full model-table outcome—not the overlay polygon by itself—controls the construction path. The table can also yield IR1 + N.C., Not Required, or Not Permitted; FireApproved’s 15 modeled material rows do not project those outcomes. That is Eagle’s book, not Idaho’s. See when the overlay map decides the eave.

The paths

  1. Statewide IBC / Idaho residential code. Spec that book unless a local WUI overlay applies.
  2. Local IWUIC or similar overlay. Spec the ordinance the building official names. Eagle 7-1G is one opened example.
  3. No WUI construction book. Harden anyway. IBHS is a designation, not adopted code.

What people mix up

  • Treating a local foothills overlay as a statewide IWUIC mandate.
  • Importing Oregon R327 or California CWUIC onto an Idaho drawing.
  • Treating this page as a parcel map. Idaho has no statewide WUI construction map on this site.

How to check

  1. Ask the building official whether the city or county adopted IWUIC or another WUI overlay, and whether your lot is in that overlay.
  2. Read 39-4109. If IWUIC is still absent, there is no statewide WUI construction book.
  3. This site does not read your parcel.

Limits

This page does not decide a permit. It does not quote a local ordinance other than the Eagle 7-1G example we opened. Listed OSFM products are California listings unless the local official accepts them.

Questions

Does Idaho require IWUIC construction on my lot today?

Not as a statewide book. Idaho Code 39-4109 adopts the IBC, the Idaho residential code, the energy code, and the IEBC. IWUIC is not on that list. Confirm with the building official.

Can my city adopt IWUIC anyway?

39-4116 says local governments that issue permits must adopt the IBC, the Idaho residential code, and the energy code. They are not required to adopt the other referenced codes in the IBC. A local ordinance may still add IWUIC. Eagle’s 2018 overlay is one opened example. See when the overlay map decides the eave. Confirm your city.

Does this site read my parcel?

No. There is no statewide WUI construction map to link. Ask the building official whether a local overlay exists.

Sources