Some tiny house builders follow particular building codes to be certified in order to meet minimum requirements of a standard house. Not all tiny house builders may follow these codes. Inquire with your builder as to what codes are followed for your tiny house.
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To gain acceptance by zoning & planning boards, tiny houses must be recognized as safely constructed. While there are standards for RVs, they are designed for recreational living, not full time residences.
The American Tiny House Association drafted guidelines for tiny houses, but some feel it would be beneficial to formalize them as true standards.
NOAH, the National Organization of Alternative Housing, developed a certification program to inspect tiny houses and ensure there are built to their specifications, which incorporate NFPA 1192, NFPA 70 NEC, ANSI A119.5.
However, one comprehensive set of tiny house standards that are fully recognized by ANSI, may be more readily accepted. To develop these, follow the ANSI Essential Requirements and become an ANSI Accredited Standards Developer.