# Buchanan · MO — IECC/Building America climate zone by U.S. county, 2021 code cycle

For Buchanan · MO, county is Buchanan; state is MO; iecc 2021 climate zone is 4; building america climate zone is Mixed‐Humid; building america zone changed from pre-2021 is Cold→Mixed‐Humid, recorded from its source on 2026-08-19.

- **County:** Buchanan _(verified: appears in the quote below)_
- **State:** MO _(our reading, not quoted from the source)_
- **IECC 2021 climate zone:** 4 _(verified: appears in the quote below)_
- **Building America climate zone:** Mixed‐Humid
- **Building America zone changed from pre-2021:** Cold→Mixed‐Humid
- **Changed from pre-2021 IECC:** 5→4 _(verified: appears in the quote below)_

## What the source says

> MO Buchanan Cold→ Mixed‐ 5→4

## Source

- https://www.osti.gov/servlets/purl/1893981

Last verified: 2026-08-19. Review by: 2028-08-18.
Part of [IECC/Building America climate zone by U.S. county, 2021 code cycle](https://referencesource.org/iecc-climate-zone-by-county/).