My dream is to own a second house. I cannot afford much, so I am thinking about buying a vacant lot and building a tiny house. The land will likely be in California. Does the law allow building a tiny house on a vacant lot California? Does it matter whether I build the tiny house on a permanent foundation or put it on a trailer with wheels?
In California, whether a tiny house is legal and if so, what conditions apply, can vary significantly between jurisdictions. What is legal in one city might not be legal in another city just down the highway. Determining whether you can build on any given piece of property will require some site-specific research.
The following answer provides some background information to help you jumpstart your research.
You will need to complete what lawyers like to call "due diligence" on each lot you are thinking about buying. In other words, do your research. Your due diligence will include at a bare minimum asking:
Hiring a local real estate agent to help with the vacant-lot purchase is a good idea. An agent can help you identify other areas of research that you need to complete and can refer you to other professionals, like attorneys or surveyors, when necessary.
In California, local governments control how land is put to use, through land use regulations. These regulations are codified in zoning codes (also known as "zoning ordinances" and "development codes".) See Building on Vacant Land: Zoning Issues You Might Face for a basic explanation of zoning.
You will want to review the zoning code to learn:
Zoning codes are not always easy to understand. If after reviewing the applicable code, you remain confused or unsure about how your property is zoned and what uses are allowed on it, do not be afraid to contact the local planning department.
Unfortunately, zoning codes in California often impose restrictions that make it difficult to get approval for tiny houses. While the regulations vary, some common hurdles tiny house developers encounter include:
The California Department of Housing and Community Development ("DHCD") issued an Information Bulletin to clarify when tiny houses may be legal to occupy. First, to be a lawful dwelling, tiny houses must be one of the following types of structures:
Second, regardless of what type of residential structure it is, the tiny house must be built to comply with certain safety standards. For example, a site-built dwelling must conform with the California Building Code (CBC). A park trailer must be built to standards promulgated by the American National Safety Institute (ANSI) and National Fire Protection Association (NFPA).
What you build your tiny house on may impact whether your tiny house is lawful on your vacant lot.
First, as the above section notes, different building and safety standards will apply. If the tiny house is built on a permanent foundation, the CBC will apply. If it is built on a trailer with wheels, it will likely meet the definition of a park trailer or recreation vehicle ("RV") and as a result, ANSI and NFPA standards will apply.
The applicable zoning code might also impose different conditions and restrictions. For instance, a stick-built tiny house that otherwise meets development standards may be lawful on a certain lot.
However, a tiny house on wheels that meets the definition of an RV might not. Instead, the RV may qualify for only temporary residential use. It also possible that it may be lawful to occupy the RV only in a mobile home park or RV park.
Given the complications you might encounter when looking for a perfect vacant lot to put your tiny house on, it could be tempting to ignore California's zoning and building codes and just throw up a tiny house. Doing so comes with significant risks, however. All it takes is one "concerned" neighbor to file a complaint or initiate a code enforcement proceeding against you. If that happens, you could find the city or county forcing you to remove your tiny house and demanding you pay a hefty fine.
A California land use attorney can help you identify applicable laws and determine whether a tiny house would be legal on the vacant land you have in mind.