Wisconsin’s first major upgrade to its Commercial Building Code in more than a decade takes effect Sept. 1, 2025, adopting 2021 International Building Code standards with state-specific adjustments. The update applies to commercial and multi-family residential buildings.

The change follows a Wisconsin Supreme Court ruling in Evers v. Marklein that struck down as unconstitutional key powers the Wisconsin Legislature had to oversee administrative rulemaking. A joint committee of the legislature had indefinitely prevented the code update from taking effect last year. As a result of the ruling, it appears the only power the Republican-controlled Legislature has left to halt or suspend a rule is to pass legislation to do so, provided Gov. Evers (D) signs the bill into law.

DSPS will accept plans under the current 2015 code through September, but all new plans submitted after Oct. 1 must meet the updated standards. The agency will also host webinars to guide industry professionals through the changes.