Maryland IRC Appendix Q Tiny Houses Statewide

Under Public Safety Article Section 12-503, the Maryland Building Performance Standards require every jurisdiction to enforce the International Residential Code. The IRC defines a tiny house as a dwelling four hundred square feet or less in floor area, excluding lofts, and Appendix Q provides reduced ceiling heights, ladder access, and emergency egress allowances when adopted. Park-model RVs and tiny houses on wheels are typically regulated as recreational vehicles under federal NFPA or ANSI standards rather than the IRC. Local jurisdictions may adopt Appendix Q or impose stricter zoning and minimum dwelling size rules but cannot drop below MBPS thresholds.

Occupying or constructing a tiny dwelling that fails to meet IRC requirements can result in code enforcement actions, denial of occupancy, condemnation, and removal orders.