You may have heard that a tiny house is under 500 square feet–or 1000 square feet. Real Estate agents routinely refer to any house under 2000 square feet as tiny. And for some, anything over 200 square feet isn’t what they consider tiny, and definitely not a proper tiny house.
So what is the official definition of a tiny house? How many square feet can it be, and still qualify as tiny? For many years there was no official definition of a tiny house–so everyone was free to make up their own definition! But recently things have changed.
As of August 2017, when the International Code Council (ICC) approved Appendix Q we got model code with an official definition of a tiny house. The 2018 International Residential Code for One- and Two-Family Dwellings (IRC) defines a tiny house as…
TINY HOUSE. A dwelling that is 400 square feet (37m2) or less in floor area excluding lofts.
That’s the entire definition. There’s nothing more to it! The thing that defines a tiny house officially, is that it’s under 400 square feet.
Of course Appendix Q only applies to tiny houses on a foundation, and not moveable tiny homes–so what about tiny houses on wheels? How big can a tiny house on wheels be? That depends on where you live, but in any state that defines a tiny house on wheels as an RV, then the maximum size for a tiny house RV is 400 square feet, according to the NFPA 1192 Standard for RVs. If you’ve ever seen a park model RV, they are often around 12′ wide and 33′ long, just under the 400 square feet maximum.
So with the IRC now defining a tiny house on a foundation as under 400 square feet. And with the ANSI Standard for RVs also allowing for a maximum of 400 square feet for tiny house RVs, it seems we now have an answer to the question of how big is a tiny home. Any home that is under 400 square feet in area, excluding lofts, whether it is on a permanent foundation or on wheels, fits the definition of a tiny house!