Building Code Information

Updates and Provision

Effective November 26, 2021, the 2021 International Codes for Building, Residential, and Swimming Pool and Spa, State of Iowa Electrical, Plumbing, Mechanical and Fuel Gas code, all with local amendments are adopted and will be enforced on all construction permits submitted and constructed thereafter in the City of Johnston. Generally, city staff made very few changes from previous code amendments and requirements; however, a published change in the shear wall bracing provisions of chapter 602.10 of the International Residential Code has been changed and will require your design attention. Additionally, please refer to the State of Iowa Energy Code for changes to return air ducting provisions and system sizing. 

Current Rules

These codes and special provisions can be updated periodically by amendments passed by the Johnston City Council.

The following codes are the adopted model codes that form the basis for the City of Johnston codes.