Standards that ensure buildings are built safely.  Building codes are made up of various sections (plumbing, electrical, etc.) These are established by the State of California and are often amended by cities.

Conditions or rules that are added to a deed for a house.  For example, some cities require homeowners to add language specifying that both the main house and second unit will not both be rented at the same time.

Permission to build a second unit or take other action that requires a public hearing.  Generally, second units do not need discretionary permits.  The opposite of a discretionary permit is a use that is allowed by right, meaning a homeowner can build their second unit as long as it meets all the standards.

Review by the city to make sure an application meets all requirements.  There is no discretion or judgment involved on a reviewer’s part and no public hearings.  Under California state law, ADUs and Junior ADUs should be approved via ministerial review by your local jurisdiction.

FAR is the number of build square feet divided by the sizes of a lot.  FAR includes build area on all floors.  The zoning code will specify the maximum FAR for your property if it applies.

The area of property that is allowed to have buildings on it in relation to the total lot area, generally expressed as a percentage.  Zoning code will specify the maximum lot coverage for your lot.

Rules that require a certain amount of yard area to be suitable for active or passive recreation (e.g. kids playing ball or a family having dinner). This requirement is identified in the zoning code.

The minimum distance a building must be located from front, side, or back property lines.  A four-foot setback means any building must be at least four feet from the side property line.   This requirement is identified in the zoning code.

Single-family zoning refers to one home on a property.  Multi-family zoning refers to more than on home located on a property (e.g., apartments).

City standards that determine what can be built on a site.  All lots in the city will be assigned a zone (e.g., R-1, a typical single-family zone), and each zone has different regulations.  The zoning code governs many aspects of development, including how tall buildings can be, where buildings can be located on a lot, etc. Most cities only allow second units in certain zoning areas.