Buying a home with an in-law unit may entail not-so-obvious risks to
both the buyer and the seller. It is important for you to understand what
it takes to have a legal secondary unit.
In order to determine requirements by the City of Oakland, I visited
the Zoning, Building and Inspection Departments. From our conversations
and the printed material they provided, it became apparent that establishing
the status of a secondary unit is a complicated matter.
Under certain conditions, an existing unit can be “made legal” even
though it may not conform to today’s zoning law. You must be able to document
that it was built prior to certain key dates.
In order for a home to qualify for a secondary unit, it must be built
on a lot not less than 5000 square feet with a width of at least 45 feet.
The unit itself must have a “floor area” between 275 and 750 square feet.
In addition, it “...will not involve an increase of more than ten percent
beyond the building’s existing floor area.”
This “ten percent rule” applies only to “expanding the existing footprint”
of the house in order to create a secondary unit. For example, if you have
a 1500 square foot split level home, the maximum you can add to the outside
of the existing structure for the purpose of developing a secondary unit
is 150 square feet. You can then take a portion of the original structure
to meet the minimum 275 square feet required for a secondary unit.
The unit must be within, or attached to, the house. It cannot be outside
the structure, e.g., a detached garage converted into an “apartment” is
not considered legal.
Bedrooms must have more than one exit, at least one working window and
a ceiling height of at least 7’6".
Two off street parking spaces are required for a single family residence.
An additional off street parking spot would be mandated for a second unit.
Depending on when it was completed, a Certificate of Occupancy for the
home may be needed.
The owner must occupy one of the units and the secondary unit cannot
be sold separately.
The secondary unit must be “clearly subordinate to the primary one-family
dwelling unit in size, location and appearance.”
There are several reasons why someone may want to avoid the process.
In Oakland, applying for a conditional use permit is a non-refundable $1356.
There is also a waiting period of about two months before the application
is reviewed. Just knowing that neighbors may register official objections
may stop a homeowner from applying.
Some individuals are reluctant to have city inspectors review and approve
all the work done to create a secondary unit. Permit procedures can be
time consuming and expensive. When work is done without permits, however,
there is nothing to prove it was completed properly and to code. This could
present health and/or safety problems, and is a major reason why illegal
in-laws can pose serious risks.
The “Report of Residential Housing Record” is the City of Oakland document
which indicates whether or not Oakland considers the unit legal. This report
is a necessity for any property that has more than one kitchen. Besides
pointing out the requirements noted above, a buyer’s agent should recommend
that the buyer insist on written approval of the 3-R Report as a condition
of the purchase contract.
A word of caution: the mere existence of a 3-R Report does not
necessarily indicate the city approves the secondary unit. It only substantiates
that a report has been ordered. It must be read carefully. If the city
has approved the secondary unit, it will be clearly spelled out on the
bottom portion of the form.
In-laws go by other names: granny flat, au pair, studio, guest quarters,
potential in-law, rental potential. Regardless of what it is called, it
is not a legal secondary unit unless the seller can document approval by
A secondary unit, if properly constructed and legal, can add value
to a property. Conversely, a poorly built, illegal unit could be considered
Anyone who buys a home with an illegal unit is also buying the potential
problems associated with it. Not all agents, and few buyers, understand
what this means. Having a competent, professional agent can be the difference
between a positive or heart-wrenching experience. Take the process seriously
and do your homework. Don’t let an in-law turn you into an outlaw.
In-Laws, Part 1;What Is A Bedroom?, How
Important Are Permits?; Buyers’
Do’s and Don’ts, Part I and Part
2; Sellers’ Do’s and Don’ts, Part
1 and Part 2; and
How To Interview Agents, Part 1,
Part 2, Part
3, and Part 4