What ceiling heights and loft sizes does the tiny house appendix require?

Where Appendix AQ is adopted, the model text sets a minimum ceiling height of 6 feet 8 inches in habitable spaces and hallways, and 6 feet 4 inches in bathrooms, toilet rooms and kitchens. Lofts may be lower. A loft used for living or sleeping needs at least 35 square feet of floor area and must be at least 5 feet in every horizontal direction; low sloped areas under 3 feet do not count toward the area. Loft access can be a stairway, ladder, alternating tread device or ship's ladder, each with its own dimensions. Local versions can be amended, as Seattle's was, so read your jurisdiction's adopted text.

Check your local rule. This varies by state, county or city. Your permitting office has the final word; the official lookup pages below show you who that is.

Sources

• 2021 Seattle Residential Code Appendix AQ: Tiny HousesCity of Seattle SDCI
• The International Residential Code has a big vision for tiny housesInternational Code Council