International Residential Code IRC

Detached 1–2 family dwellings and townhouses up to 3 stories above grade. Anything larger falls under the IBC.

Overview

Detached 1–2 family dwellings and townhouses up to 3 stories above grade. Anything larger falls under the IBC.

Publisher
International Code Council (ICC)
Latest edition
2024
First published
2000
Cycle
Every 3 years

Why it matters

The IRC is where the for-sale single-family and townhouse rules live — floor loads, stair geometry, egress windows, R-values by climate zone. For build-to-rent horizontal developers, this is the governing code.

Adoption by edition

Each row is one published edition, with the states (and DC) that have adopted it as the statewide minimum. Click a postal code to jump to that state's code wiki.

EditionStatesAdopting jurisdictions
20248CA · GA · IA · NV · NY · ND · UT · WY
202122AL · AR · CT · FL · LA · ME · MD · MA · MT · NH · NJ · NM · OH · OR · PA · RI · SC · VT · VA · WA · WV · WI
20201ID
20188AK · DE · HI · IN · MN · NE · OK · TN
20151MI
20122MS · TX
20091KY

Local amendments

Climate-zone insulation tables, radon mitigation, storm-shelter and wildland-urban-interface additions are common local amendments.