The International Code Council and Tiny Home Industry Association (THIA) will collaborate to update the existing provisions on tiny houses contained in the International Residential Code (IRC), Appendix AQ through the standards development process. The content of ICC/THIA Standard 1215: Design, Construction, Inspection and Regulation of Tiny Houses for Permanent Occupancy will continue to cover tiny houses used for permanent occupancy on a foundation or on wheels as addressed in the IRC. The standard will be developed through the Code Council’s ANSI-consensus procedures, requiring essential engagement from all industry stakeholders and allowing for an in-depth examination of technical or emerging issues.

ICC/THIA Standard 1215 will be based on existing requirements contained in the 2021 International Residential Code (IRC), including Appendix AQ and ICC/MBI Standards 1205 and 1200 where applicable, and will continue to be published in the IRC as Appendix AQ, as well as a standalone resource. As a standard, the criteria outlined in these documents will be more readily adoptable internationally and in jurisdictions that do not use the IRC as its base code. The Code Council has submitted a Project Initiation Notification System (PINS) notice to the American National Standards Institute (ANSI) for the development of an American National Standard.

The standard complements the work of ASTM’s recently established E06.26 Subcommittee on Tiny Houses by combining existing criteria for tiny houses used for permanent occupancy into a single, referenceable location. Ryan Colker, Code Council vice president of innovation, David Tompos, president of ICC-NTA, and Brad Wiseman, CEO and board chairman of THIA, are members of this ASTM subcommittee and will work alongside other members to ensure that the Code Council and ASTM efforts avoid overlap and complement each other, in addition to providing consistency and clarity for tiny house builders, code officials and municipalities on corresponding codes and standards.

“This new standard will codify existing requirements for the design, construction, inspection and certification of tiny houses into a single standard while also helping to address identified gaps in available requirements,” Colker said.

“This joint effort with the Code Council will go a long way in helping to clear the confusion within the regulatory and tiny home builder community,” Wiseman said.

Understanding the need for requirements specific to tiny houses, the Code Council first introduced Appendix AQ, previously called Appendix Q, into the 2018 IRC. This appendix was the first set of building standards for dwellings ever incorporated into a model code.

ICC/THIA Standard 1215 will complement existing tiny house resources developed by the Code Council, including the International Tiny House Provisions, Model Legislation on Tiny Houses, and a Guide on Navigating Certification and Regulation of Tiny Houses. All of these are available on the Code Council’s dedicated off-site construction webpage.