Bill Text: IA HSB162 | 2025-2026 | 91st General Assembly | Introduced
Bill Title: A bill for an act relating to county and city regulation of accessory dwelling units.
Spectrum: Committee Bill
Status: (Introduced) 2025-02-26 - Subcommittee recommends amendment and passage. [HSB162 Detail]
Download: Iowa-2025-HSB162-Introduced.html
House
Study
Bill
162
-
Introduced
HOUSE
FILE
_____
BY
(PROPOSED
COMMITTEE
ON
LOCAL
GOVERNMENT
BILL
BY
CHAIRPERSON
JONES)
A
BILL
FOR
An
Act
relating
to
county
and
city
regulation
of
accessory
1
dwelling
units.
2
BE
IT
ENACTED
BY
THE
GENERAL
ASSEMBLY
OF
THE
STATE
OF
IOWA:
3
TLSB
1834YC
(1)
91
ll/js
H.F.
_____
Section
1.
Section
331.301,
Code
2025,
is
amended
by
adding
1
the
following
new
subsection:
2
NEW
SUBSECTION
.
27.
a.
A
county
shall
adopt
an
ordinance,
3
motion,
resolution,
or
amendment
that
allows
a
minimum
of
one
4
accessory
dwelling
unit
on
the
same
lot
as
a
single
family
5
residence
in
accordance
with
the
following
conditions:
6
(1)
An
accessory
dwelling
unit
shall
comply
with
all
7
applicable
building
regulations
as
defined
in
section
103A.3.
8
(2)
An
accessory
dwelling
unit
shall
be
prohibited
or
9
limited
only
to
the
extent
that
a
state
historic
building
code
10
restriction,
as
adopted
by
a
county
in
accordance
with
section
11
103A.43,
subsection
3,
a
deed
restriction,
or
a
rule
of
a
12
common
interest
community,
as
defined
in
section
499C.1,
limits
13
or
prohibits
the
construction
or
use
of
an
accessory
dwelling
14
unit.
The
imposition
of
an
ordinance,
motion,
resolution,
or
15
amendment
regulating
accessory
dwelling
units
that
is
more
16
restrictive
when
applied
to
a
common
interest
community
than
17
when
applied
to
a
single
family
residence
is
prohibited.
18
(3)
If
a
manufactured
home
as
defined
in
section
435.1,
19
subsection
3,
or
a
mobile
home
as
defined
in
section
435.1,
20
subsection
5,
is
used
as
an
accessory
dwelling
unit,
the
21
manufactured
home
or
mobile
home
shall
be
converted
to
real
22
property
by
being
placed
on
a
permanent
foundation
and
assessed
23
for
real
estate
taxes
pursuant
to
section
435.26.
24
b.
Except
as
otherwise
provided
in
paragraph
“a”
or
by
state
25
law,
a
county
shall
not
impose
any
of
the
following
limitations
26
or
restrictions:
27
(1)
A
requirement
that
an
accessory
dwelling
unit
be
smaller
28
than
one
thousand
square
feet.
However,
a
county
may
prohibit
29
the
accessory
dwelling
unit
from
being
larger
than
the
single
30
family
residence.
31
(2)
Requirements
related
to
the
placement
or
appearance
of
32
an
accessory
dwelling
unit
that
are
more
restrictive
than
those
33
imposed
on
a
single
family
residence
including
but
not
limited
34
to
the
following:
maximum
building
heights;
minimum
setback
35
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9
H.F.
_____
requirements;
minimum
lot
sizes;
minimum
building
frontages;
1
maximum
lot
coverages;
density
requirements;
and
aesthetic
2
or
architectural
standards
or
requirements.
Additionally,
a
3
county
shall
not
require
an
accessory
dwelling
unit
to
match
4
the
exterior
design,
roof
pitch,
or
finishing
materials
of
the
5
single
family
residence.
6
(3)
Regulations
on
the
use
of
an
accessory
dwelling
unit
as
7
a
rental
property
that
are
more
restrictive
than
those
provided
8
for
in
subsection
18
of
this
section
and
chapter
562A.
9
(4)
A
requirement
that
the
lot
containing
a
single
family
10
residence
and
an
accessory
dwelling
unit
have
additional
11
parking
beyond
that
required
for
a
single
family
residence
or
12
payment
of
a
fee
in
lieu
of
providing
additional
parking.
13
(5)
Restrictions
on
the
occupancy
of
either
the
single
14
family
residence
or
the
accessory
dwelling
unit
by
any
of
15
the
following
manners:
requiring
the
property
owner
to
be
16
a
resident;
requiring
a
familial,
marital,
or
employment
17
relationship
to
exist
between
the
occupants
of
the
single
18
family
residence
and
the
occupants
of
the
accessory
dwelling
19
unit;
or
restricting
the
occupancy
of
an
accessory
dwelling
20
unit
based
on
income
or
age.
21
(6)
The
requirement
of
new
or
separate
utility
lines
22
between
the
accessory
dwelling
unit
and
public
utility
service
23
connections.
However,
if
full
utility
access
that
includes
24
a
separate
metering
system
for
billing
purposes
cannot
be
25
provided
to
the
accessory
dwelling
unit,
then
the
county
can
26
require
new
or
separate
utility
lines.
27
(7)
Prohibition
of
the
construction
of
an
accessory
28
dwelling
unit
as
it
relates
to
the
timing
of
the
construction
29
of
the
single
family
residence
on
the
same
lot.
An
accessory
30
dwelling
unit
can
be
constructed
before,
during,
or
after
the
31
construction
of
the
single
family
residence.
32
(8)
Imposition
of
a
different
county
impact
fee
structure
or
33
development
standard
for
an
accessory
dwelling
unit
than
those
34
used
for
the
single
family
residence
on
the
same
lot.
35
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2/
9
H.F.
_____
(9)
The
requirement
of
improvements
or
repairs
to
public
1
streets
or
sidewalks
beyond
those
imposed
on
the
single
family
2
residence
on
the
same
lot.
3
c.
A
county
shall
approve
an
accessory
dwelling
unit
permit
4
application
that
meets
the
requirements
set
forth
in
paragraph
5
“a”
and
by
state
law
without
discretionary
review
or
hearing
6
and
consistent
with
the
time
frame
assigned
to
the
approval
7
of
a
single
family
residence.
An
accessory
dwelling
unit
8
permit
application
not
approved
or
denied
within
thirty
days
of
9
receipt
shall
be
deemed
approved
by
the
county.
If
the
county
10
denies
an
accessory
dwelling
unit
permit,
the
reason
for
denial
11
shall
be
provided
in
writing
to
the
applicant
and
include
any
12
remedy
necessary
to
secure
approval.
13
d.
A
county
ordinance,
motion,
resolution,
or
amendment
14
regulating
accessory
dwelling
units
in
a
manner
that
conflicts
15
with
this
subsection
is
void.
Nothing
in
this
subsection
16
prohibits
a
county
from
adopting
an
ordinance,
motion,
17
resolution,
or
amendment
that
is
more
permissive
than
the
18
requirements
provided
in
this
subsection.
19
e.
For
the
purposes
of
this
subsection:
20
(1)
“Accessory
dwelling
unit”
means
an
additional
21
residential
dwelling
unit
located
on
the
same
lot
as
a
single
22
family
residence
that
is
either
attached
to
or
detached
from
23
the
single
family
residence.
24
(2)
“Detached”
includes
being
part
of
any
accessory
25
structure
such
as
a
detached
garage.
26
(3)
“Dwelling
unit”
means
the
same
as
defined
in
section
27
562A.6,
subsection
3.
28
(4)
“Single
family
residence”
means
the
same
as
defined
29
in
section
562A.6,
subsection
15,
except
to
the
extent
that
30
a
single
family
residence
may
share
utility
lines
with
the
31
accessory
dwelling
unit
if
full
utility
access
that
includes
a
32
separate
metering
system
for
billing
purposes
can
be
provided
33
to
the
accessory
dwelling
unit.
34
Sec.
2.
Section
364.3,
Code
2025,
is
amended
by
adding
the
35
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H.F.
_____
following
new
subsection:
1
NEW
SUBSECTION
.
20.
a.
A
city
shall
adopt
an
ordinance,
2
motion,
resolution,
or
amendment
that
allows
a
minimum
of
one
3
accessory
dwelling
unit
on
the
same
lot
as
a
single
family
4
residence
in
accordance
with
the
following
conditions:
5
(1)
An
accessory
dwelling
unit
shall
comply
with
all
6
applicable
building
regulations
as
defined
in
section
103A.3.
7
(2)
An
accessory
dwelling
unit
shall
be
prohibited
or
8
limited
only
to
the
extent
that
a
state
historic
building
code
9
restriction,
as
adopted
by
a
city
in
accordance
with
section
10
103A.43,
subsection
3,
a
deed
restriction,
or
a
rule
of
a
11
common
interest
community,
as
defined
in
section
499C.1,
limits
12
or
prohibits
the
construction
or
use
of
an
accessory
dwelling
13
unit.
The
imposition
of
an
ordinance,
motion,
resolution,
or
14
amendment
regulating
accessory
dwelling
units
that
is
more
15
restrictive
when
applied
to
a
common
interest
community
than
16
when
applied
to
a
single
family
residence
is
prohibited.
17
(3)
If
a
manufactured
home
as
defined
in
section
435.1,
18
subsection
3,
or
a
mobile
home
as
defined
in
section
435.1,
19
subsection
5,
is
used
as
an
accessory
dwelling
unit,
the
20
manufactured
home
or
mobile
home
shall
be
converted
to
real
21
property
by
being
placed
on
a
permanent
foundation
and
assessed
22
for
real
estate
taxes
pursuant
to
section
435.26.
23
b.
Except
as
otherwise
provided
in
paragraph
“a”
or
by
state
24
law,
a
city
shall
not
impose
any
of
the
following
limitations
25
or
restrictions:
26
(1)
A
requirement
that
an
accessory
dwelling
unit
be
smaller
27
than
one
thousand
square
feet.
However,
a
city
may
prohibit
28
the
accessory
dwelling
unit
from
being
larger
than
the
single
29
family
residence.
30
(2)
Requirements
related
to
the
placement
or
appearance
of
31
an
accessory
dwelling
unit
that
are
more
restrictive
than
those
32
imposed
on
a
single
family
residence
including
but
not
limited
33
to
the
following:
maximum
building
heights;
minimum
setback
34
requirements;
minimum
lot
sizes;
minimum
building
frontages;
35
-4-
LSB
1834YC
(1)
91
ll/js
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9
H.F.
_____
maximum
lot
coverages;
density
requirements;
and
aesthetic
1
or
architectural
standards
or
requirements.
Additionally,
a
2
city
shall
not
require
an
accessory
dwelling
unit
to
match
the
3
exterior
design,
roof
pitch,
or
finishing
materials
of
the
4
single
family
residence.
5
(3)
Regulations
on
the
use
of
an
accessory
dwelling
unit
as
6
a
rental
property
that
are
more
restrictive
than
those
provided
7
for
in
subsections
9
and
16
of
this
section,
section
414.1,
8
subsection
1,
paragraph
“e”
,
and
chapter
562A.
9
(4)
A
requirement
that
the
lot
containing
a
single
family
10
residence
and
an
accessory
dwelling
unit
have
additional
11
parking
beyond
that
required
for
a
single-family
residence
or
12
payment
of
a
fee
in
lieu
of
providing
additional
parking.
13
(5)
Restrictions
on
the
occupancy
of
either
the
single
14
family
residence
or
the
accessory
dwelling
unit
by
any
of
15
the
following
manners:
requiring
the
property
owner
to
be
16
a
resident;
requiring
a
familial,
marital,
or
employment
17
relationship
to
exist
between
the
occupants
of
the
single
18
family
residence
and
the
occupants
of
the
accessory
dwelling
19
unit;
or
restricting
the
occupancy
of
an
accessory
dwelling
20
unit
based
on
income
or
age.
21
(6)
A
requirement
of
new
or
separate
utility
lines
between
22
the
accessory
dwelling
unit
and
public
utility
service
23
connections.
However,
if
full
utility
access
that
includes
24
a
separate
metering
system
for
billing
purposes
cannot
be
25
provided
to
the
accessory
dwelling
unit,
then
the
city
can
26
require
new
or
separate
utility
lines.
27
(7)
Prohibition
of
the
construction
of
an
accessory
28
dwelling
unit
as
it
relates
to
the
timing
of
the
construction
29
of
the
single
family
residence
on
the
same
lot.
An
accessory
30
dwelling
unit
can
be
constructed
before,
during,
or
after
the
31
construction
of
the
single
family
residence.
32
(8)
Imposition
of
a
different
city
impact
fee
structure
or
33
development
standard
for
an
accessory
dwelling
unit
than
those
34
used
for
the
single
family
residence
on
the
same
lot.
35
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LSB
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91
ll/js
5/
9
H.F.
_____
(9)
The
requirement
of
improvements
or
repairs
to
public
1
streets
or
sidewalks
beyond
those
imposed
on
the
single
family
2
residence
on
the
same
lot.
3
c.
A
city
shall
approve
an
accessory
dwelling
unit
permit
4
application
that
meets
the
requirements
set
forth
in
paragraph
5
“a”
and
by
state
law
without
discretionary
review
or
hearing
6
and
consistent
with
the
time
frame
assigned
to
the
approval
7
of
a
single
family
residence.
An
accessory
dwelling
unit
8
permit
application
not
approved
or
denied
within
thirty
days
9
of
receipt
shall
be
deemed
approved
by
the
city.
If
the
city
10
denies
an
accessory
dwelling
unit
permit,
the
reason
for
denial
11
shall
be
provided
in
writing
to
the
applicant
and
include
any
12
remedy
necessary
to
secure
approval.
13
d.
A
city
ordinance,
motion,
resolution,
or
amendment
14
regulating
accessory
dwelling
units
in
a
manner
that
conflicts
15
with
this
subsection
is
void.
Nothing
in
this
subsection
16
prohibits
a
city
from
adopting
an
ordinance,
motion,
17
resolution,
or
amendment
that
is
more
permissive
than
the
18
requirements
provided
in
this
subsection.
19
e.
For
the
purposes
of
this
subsection:
20
(1)
“Accessory
dwelling
unit”
means
an
additional
21
residential
dwelling
unit
located
on
the
same
lot
as
a
single
22
family
residence
that
is
either
attached
to
or
detached
from
23
the
single
family
residence.
24
(2)
“Detached”
includes
being
part
of
an
accessory
structure
25
such
as
a
detached
garage.
26
(3)
“Dwelling
unit”
means
the
same
as
defined
in
section
27
562A.6,
subsection
3.
28
(4)
“Single
family
residence”
means
the
same
as
defined
29
in
section
562A.6,
subsection
15,
except
to
the
extent
that
30
a
single
family
residence
may
share
utility
lines
with
the
31
accessory
dwelling
unit
if
full
utility
access
that
includes
a
32
separate
metering
system
for
billing
purposes
can
be
provided
33
to
the
accessory
dwelling
unit.
34
EXPLANATION
35
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The
inclusion
of
this
explanation
does
not
constitute
agreement
with
1
the
explanation’s
substance
by
the
members
of
the
general
assembly.
2
This
bill
provides
that
a
county
or
city
shall
adopt
an
3
ordinance,
motion,
resolution,
or
amendment
that
allows
a
4
minimum
of
one
accessory
dwelling
unit
(ADU)
on
the
same
5
lot
as
a
single
family
residence.
The
ADU
shall
comply
6
with
all
applicable
building
regulations
as
defined
in
Code
7
section
103A.3,
and
shall
be
prohibited
or
limited
to
the
8
extent
that
a
state
historic
building
code
restriction,
as
9
adopted
by
a
county
or
city
in
accordance
with
Code
section
10
103A.43,
subsection
3,
a
deed
restriction,
or
a
rule
of
a
11
common
interest
community,
as
defined
in
Code
section
499C.1,
12
limits
or
prohibits
the
construction
or
use
of
an
ADU.
The
13
imposition
of
an
ordinance,
motion,
resolution,
or
amendment
14
regulating
ADUs
that
is
more
restrictive
when
applied
to
a
15
common
interest
community
than
when
applied
to
a
single
family
16
residence
is
prohibited.
If
a
manufactured
home
as
defined
in
17
Code
section
435.1,
subsection
3,
or
a
mobile
home
as
defined
18
in
Code
section
435.1,
subsection
5,
is
used
as
an
ADU,
the
19
manufactured
home
or
mobile
home
shall
be
converted
to
real
20
property
by
being
placed
on
a
permanent
foundation
and
assessed
21
for
real
estate
taxes
pursuant
to
Code
section
435.26.
22
A
county
or
city
shall
not
impose
any
of
the
following
23
limitations
or
restrictions:
a
requirement
that
an
ADU
be
24
smaller
than
1,000
square
feet;
requirements
related
to
the
25
placement
or
appearance
of
an
ADU
that
are
more
restrictive
26
than
those
imposed
on
a
single
family
residence
including
27
maximum
building
heights,
minimum
setback
requirements,
minimum
28
lot
sizes,
minimum
building
frontages,
maximum
lot
coverages,
29
density
requirements,
and
aesthetic
or
architectural
standards
30
or
requirements;
regulations
on
the
use
of
an
ADU
as
a
rental
31
property
that
are
more
restrictive
than
those
provided
for
32
in
Code
section
331.301,
subsection
18,
for
counties,
Code
33
section
364.3,
subsections
9
and
16,
and
Code
section
414.1,
34
subsection
1,
paragraph
“e”,
for
cities;
and
Code
chapter
35
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562A;
a
requirement
that
the
lot
containing
a
single
family
1
residence
and
an
ADU
have
additional
parking
beyond
that
2
required
for
a
single
family
residence
or
payment
of
a
fee
in
3
lieu
of
providing
additional
parking;
the
requirement
of
new
or
4
separate
utility
lines
between
the
ADU
and
public
or
private
5
utility
service
connections;
prohibition
of
the
construction
6
of
an
ADU
as
it
relates
to
the
timing
of
the
construction
of
7
the
single
family
residence
on
the
same
lot;
imposition
of
8
a
different
county
or
city
impact
fee
structure
for
an
ADU
9
than
the
one
used
for
the
single
family
residence
on
the
same
10
lot;
and
the
requirement
of
improvements
or
repairs
to
public
11
streets
or
sidewalks
beyond
those
imposed
on
the
single
family
12
residence
on
the
same
lot.
13
A
county
or
city
cannot
impose
restrictions
on
the
occupants
14
of
either
the
single
family
residence
or
the
ADU
by
any
15
the
following
manners:
requiring
the
property
owner
to
be
16
a
resident;
requiring
a
familial,
marital,
or
employment
17
relationship
to
exist
between
the
occupants
of
the
single
18
family
residence
and
the
occupants
of
the
ADU;
and
restricting
19
the
occupancy
of
an
ADU
based
on
income
or
age.
A
county
or
20
city
shall
not
require
an
ADU
to
match
the
exterior
design,
21
roof
pitch,
or
finishing
materials
of
the
single
family
22
residence.
A
county
or
city
may
prohibit
the
ADU
from
being
23
larger
than
the
single
family
residence
on
the
same
lot.
If
24
full
utility
access
that
includes
a
separate
metering
system
25
for
billing
purposes
cannot
be
provided
to
the
ADU
then
the
26
county
or
city
can
require
new
or
separate
utility
lines
27
between
the
ADU
and
public
utility
service
connections.
28
A
county
or
city
must
approve
an
ADU
permit
application
29
that
meets
the
necessary
requirements
without
discretionary
30
review
or
hearing
and
consistent
with
the
time
frame
assigned
31
to
the
approval
of
a
single
family
residence.
An
ADU
permit
32
application
not
approved
or
denied
within
30
days
of
receipt
33
shall
be
deemed
approved
by
the
county
or
city.
If
the
county
34
or
city
denies
an
ADU
permit,
the
reason
for
denial
must
be
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provided
in
writing
to
the
applicant
and
include
any
remedy
1
necessary
to
secure
approval.
A
county
or
city
ordinance,
2
motion,
resolution,
or
amendment
regulating
ADUs
in
a
manner
3
that
conflicts
with
the
bill
is
void.
A
county
or
city
can
4
adopt
an
ordinance,
motion,
resolution,
or
amendment
that
is
5
more
permissive
than
the
requirements
provided
in
the
bill.
6
For
the
purposes
of
the
bill,
“accessory
dwelling
unit”
7
means
an
additional
residential
dwelling
unit
located
on
the
8
same
lot
as
a
single
family
residence
that
is
either
attached
9
to
or
detached
from
the
single
family
residence;
“detached”
10
includes
being
part
of
any
accessory
structure
such
as
a
11
detached
garage;
“dwelling
unit”
means
a
structure
or
the
12
part
of
a
structure
that
is
used
as
a
home,
residence,
or
13
sleeping
place;
and
“single
family
residence”
means
a
structure
14
maintained
and
used
as
a
single
dwelling
unit,
even
if
the
15
structure
shares
utility
lines
with
the
ADU
if
full
utility
16
access
that
includes
a
separate
metering
system
for
billing
17
purposes
is
provided
to
the
ADU.
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