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Tiny Houses

Tiny House

Many property owners are interested in using tiny houses or tiny homes to house themselves or to rent out. Small homes can provide much-needed cost-effective and energy-efficient housing, and can be a creative solution to the current housing crisis.

But before you buy a tiny house yourself, be sure that you ask the right questions. There is no industry standard definition of a tiny house. The term is used to describe a variety of dwelling types, and the permitting and inspection requirements differ for each type of tiny house. Here are some terms to get you started:

  • Stick-built/site-constructed homes: A small home constructed entirely at the building site.
  • Manufactured houses (commonly referred to as mobile homes): Homes built in a factory mounted on a non-removable steel chassis or frame.
  • Factory-built houses (commonly referred to as modular homes): Factory-constructed homes that are transported to a permanent location for installation on a foundation.
  • Recreation Vehicles: Travel trailers, motor homes, park model homes, truck campers, camping trailers, or any other housing on wheels.

International Residential Code (IRC) Definition

According to the 2018 International Residential Code (IRC), a tiny house is a dwelling that is 400 square feet or less in floor area excluding lofts. The 2018 IRC Appendix Q outlines some code requirements for tiny houses. In addition to IRC requirements, tiny houses permitted by Sonoma County must meet the building regulations found in the current California Building Codes and Chapter 7 of the Sonoma County Municipal Code.

Review and Approval Requirements

There are distinct review and approval requirements for the different types of tiny houses as outlined below:

Planning Division Requirements for Use of Tiny Homes

Accessory Dwelling Units

If a tiny home on a permanent foundation is proposed to be used as an accessory dwelling unit (i.e., in addition to a primary residence), it must meet the requirements in State law. Recreational vehicles (RVs) do not qualify.

Cottage Housing Developments

Tiny homes on permanent foundations may be used as cottage housing developments in accordance with the Cottage Housing Ordinance. Recreational vehicles (RVs) do not qualify.

Agricultural Housing

Tiny homes on permanent foundations may be used for agricultural housing. Recreational vehicles (RVs) may qualify for temporary farmworker housing.

Special Occupancy Parks

Organized Camp vs. Special Occupancy Park