What is a Second Dwelling Unit?
A Second Dwelling Unit (aka, “in-law” or “granny” unit) is an additional dwelling located on the same lot as a single-family residence which contains separate living/sleeping, sanitary, and cooking facilities. A second unit may be located within the principal dwelling or can be in a detached accessory building. The unit cannot be sold separately from the principal dwelling.
What is the Review Process?
Second units are subject to ministerial review by the Planning Division prior to issuance of a building permit. Additional zoning entitlements may be required, as specified in San Rafael Municipal Code Section 14.16.285. A second unit review fee ($_____) and application form along with project plans (___ sets) must be submitted to the Planning Division which will verify whether the unit complies with the Second Unit Performance Standards. If building permit clearance is granted, a Second Unit deed restriction must be recorded for the property.
Can an Existing (Unpermitted) Second Unit be legalized?
Yes. The unit must meet all requirements for a second unit, and obtain planning review of a Second Dwelling Unit. Building permit fees to legalize an existing unauthorized second unit will be tripled and planning fees will be doubled.
What are the Rules for Legal Conforming or Non-conforming Second Dwelling Units?
A an existing unit constructed and established prior to adoption of zoning regulations for second units may be protected under Section 14.16.060 (Conservation of Dwelling Units). To determine applicability, the owner must produce evidence that the unit was either legally established prior to 1950 (prior to adoption of the City’s first Zoning Code) or constructed prior to January 1, 1991. This may require submittal of documentation and a zoning determination request to the Planning Division. Typically, evidence is provided through building permit records. If such records do not exist, evidence could include documentation of the residential building record used for assessment purposes, which may be obtained from the County Assessor’s office.
What are the Building Permit Requirements?
The unit must have a separate address and ‘path of travel’ to and from a public way. For an attached unit, there must be a “1-hour separation” between the unit and main residence. The unit must have a separate heating control system. A detached unit must have its own minimum 60 amp feed for power. All rooms must meet minimum standards for light and ventilation. All “sleeping rooms” must have direct access (window or door) to the outside.
Minimum dimensions for living units are as follows:
- Studio: 220 sq. ft. (not incl. closet and bathroom).
- One, plus bedrooms: Main room - 120 sq. ft. / 7 ft. min. dimension. Other rooms (except kitchens) - 70 sq. ft. / 7 ft. min. dimension.
- Ceiling height for habitable rooms is 7.5 ft., and kitchen, hallways, & bathroom is 7 ft.
A suitable kitchen facility must be separate from the bathroom and provide a sink, cooking facility (more than a hot plate or microwave), refrigeration and storage. A suitable bathroom facility must include a toilet, sink and bathing facilities.
Density/Min. Lot Size
A minimum 5,000 square foot lot size developed with a single-family residence is required in order to qualify for a second unit. Only one second unit (or junior unit) is allowed in addition to the main unit per lot.
The property owner must reside in either the principal or the second unit.
A deed restriction must be recorded with the County Recorder so that future owners of the property will be aware of the requirements (such as owner occupancy).Proof of recordation must be submitted to the Planning Division prior to issuance of a building permit or after Second Unit application has been processed.
At no time shall the size of the second unit exceed 40% of the gross square footage of the principal dwelling, excluding the garage, except that the floor area of a second unit may be a minimum of 500 square feet, regardless of the size of the house. The maximum size of a second unit is 1,000 square feet provided that any second unit over 800 square feet in size also requires Planning Commission Use Permit approval.
If the unit is added to a principal single-family dwelling, the height limit is 30 feet above grade. If a unit is proposed as an accessory structure, the height limit is 15 feet. (I.e., consistent with the underlying zoning district standards for height limits and measurement). Note that Use Permit and/or Design Review permits may be required for second units in accessory structures that exceed the height limit.
Second dwelling units added or attached to the principal residence shall be subject to the setback requirements otherwise applicable to the principal residential structure. Second dwelling units constructed as a separate detached accessory building shall be subject to the setback requirements otherwise applicable to accessory structures. Note that Use Permit and/or Design Review permits may be required for second units in accessory structures that are located within the required setbacks.
Review and approval of a discretionary Environmental and Design Review Permit by the Planning Commission pursuant to Chapter 14.25 will be required for any second unit proposed as follows:
- An upper story addition to the main residence that exceeds 500sf
- A detached unit that is two-stories
- A detached unit located within side or rear yard setbacks required for the main structure setbacks
- New construction on a lot subject to the Hillside Overlay (-H) District Development regulations; if required
- for the addition per Chapter’s 14.12 and 14.25
Note: Upon application for review, the Community Development Directory may propose to downgrade review to the Zoning Administrator level, if a concurrent Use Permit is not required.
Review and approval of a discretionary Use Permit by the Planning Commission is required for any second unit proposed as follows:
- A detached unit that exceeds the 15 foot height limit and/or located within side or rear yard setbacks required for the main structure
- A second unit that exceeds 800 square feet in size (up 1,000 square feet)
Studio or 1-bedroom second unit: 1 space 2 or more-bedroom second unit: 2 spaces Parking for the second unit may be uncovered. One parking space for the second unit may be in the front yard on a paved area between the driveway and the nearest side property line, parallel to the driveway. On parcels having frontage on a street with a paved width of at least 38 feet, one parking space for the second unit may be tandem (located behind a parking space for the principal dwelling), located on a driveway which is at least 18 feet in length behind the property line.
Prior to approval a City planner will review the design plans (and visit the project site in the case of legalizing a second unit) to ensure that the second unit incorporates the same or similar exterior colors, architectural detailing, roof pitch same or similar and exterior materials, and window style, as the structure containing the principal residence.
The second unit must have a separate entrance from the principal dwelling. In order to maintain the appearance of a single-family residence, the entrances to the second unit and principal dwelling unit cannot be located on the same side (elevation) of the principal dwelling most parallel to the front property line.