HomeMy WebLinkAboutPlanning 2017-10-26 Item 4 - Accessory Dwelling Unit Regulation - Attachment A: Homelessness and Housing Toolkit for CitiesHomelessness & housing
toolkit for cities
Tools and resources to
address homelessness
and affordable housing
from real cases in cities
across Washington.
ewe
ASSOCIATION
OFiWASHINGTON I M RSC
Affordable housing
Revising city regulations to encourage
accessory dwelling units
Accessory dwelling units (ADUs) have
been around for decades. In many
parts of Washington State, the concept
is accepted and local governments
have revised their regulations to
accommodate such housing. Even
so, the number of ADUs created in
accordance with local standards has
remained relatively low, due in part
to the difficulty in meeting those
regulations and the associated costs.
In response, a few local governments
are relooking at their standards and
discussing how to make them easier to
meet.The potential easing of existing
ADU regulations, however, is causing
neighborhood homeowners to take
notice.
What is an accessory
dwelling unit (ADU)?
An accessory dwelling unit (ADU)
is a small, self-contained residential
unit located on the same lot as an
existing single-family home. They are
sometimes referred to as "mother-in-
law apartments.' An ADU has all the
basic facilities needed for day-to-day
living independent of the main home,
such as a kitchen, sleeping area, and a
bathroom.
16
There are two types of ADUs:
1. Attached ADU, which may be
created as either:
a. A separate unit within an existing
home (such as in an attic or
basement); or
b. An addition to the home (such as
a separate apartment unit with
its own entrance).
2. Detached ADU, created in a
separate structure on the lot (such
as a converted garage or a new
"backyard cottage").
Reasons for allowing ADUs
State law (RCW 43.63A.215 and RCW
36.70A.400) requires that certain cities
and counties adopt ordinances to
encourage the development of ADUs
in single-family zones, by incorporating
the model ordinance recommendations
prepared by the Washington
Department of Commerce. In addition
to just meeting a statutory mandate,
however, ADUs have also helped
local jurisdictions meet their Growth
Management Act goals to encourage
affordable housing and provide a variety
of housing densities and types, while
still preserving the character of single-
family neighborhoods. From a planning
perspective, it is considered by many
to be a "kinder and gentler" method for
accommodating population growth in
a community, as compared to upzoning
land to do so.
15
Standard ADU regulations
Most local ADU regulations have
standards to address the following
issues:
• Maximum unit size
• Owner -occupancy
Dedicated off-street parking
Attached ADUs only
• Maximum number of dwelling units
on one lot
• Separate entrances/Only one visible
from the street
• Other design standards (especially
for detached ADUs) for such items
as roof pitch, window style, and
exterior material
Maximum number of occupants
Minimum lot size
• Building code and other"life/safety"
requirements
Communities starting
to reconsider ADU
requirements
Some local governments in Washington
State and elsewhere are reexamining
their"standard"ADU requirements and
questioning the rationale behind them,
especially given the low production
rate of new accessory dwelling units.
As a result, some communities are
considering changes to ADU regulations,
such as:
• Unit size: Most current ADU
standards set a maximum size (for
example, 800 square feet), but some
communities are considering an
increase to their limit to provide
more flexibility.
• On-site parking: Some local
governments are looking at
a reduction or elimination of
standards requiring on-site parking
spaces for the ADU's occupants,
especially in areas where there
is adequate on -street parking.
Such a change may face stronger
opposition in neighborhood where
street parking is at a premium.
• Detached ADUs: Most codes
only allow attached ADUs, but
more communities are expanding
regulations to permit detached
ADUs (which are usually required
to be placed in the back half of a
residential lot). Even if allowed, the
high cost of constructing "backyard
cottages" may limit the number that
actually get built.
• Owner -occupancy: Most codes
require that the property owner
needs to occupy either the primary
or accessory unit, but some
communities (such as Seattle)
are considering removing this
requirement.
• Allowing more than two dwelling
units: A"cutting edge" regulatory
change is to increase the maximum
number of dwelling units on a single
family lot to three (by allowing
one primary dwelling unit, one
attached ADU, and one detached
ADU). In Seattle, the City Council
is currently considering proposed
code revisions that would include
an increase to three units on one lot.
Discussion about these types of
changes has caused anxiety for some
homeowners, who are concerned about
the impacts on neighborhood character
and property values. On the other side
are affordable housing advocates who
consider changing existing regulations
as a way to effectively increase the
number of legal ADUs.
Regardless of how local governments
decide to regulate them, ADUs may
be a viable approach to address a
community's growth and affordable
housing policies in a manner that is
acceptable to residents (especially if they
16
consider the alternatives). Just be sure
regulations and development review
process aren't so burdensome that
property owners end up not creating
these dwelling units or building an ADU
without obtaining the required permits.
Resources
l Accessory Dwellings website
www.accessorydwellings.org
i
1
MRSC's Accessory Dwelling
Units: Issues & Options
publication
www.mrsc.org
MRSC's Accessory Dwelling
Units and Affordable Housing
webpages
www.mrsc.org
17