Chapter
14.06
RI-I0
SINGLE-FAMILY
DISTRICT
Sections:
14.06.0lO
RI-lO
District.
14.06.020
Permitted uses
(Rl-I0).
14.06.030
Conditional uses
(Rl-lO).
14.06.040 Site area (R1-tO).
14.06.050 Site frontage, width and depth
(RI-IO).
14.06.060
Coverage (RI-tO).
14.06.070
Floor
area
ratio (R
I-I
OJ
.
14.06.080
Setbacks
(R
I-I
OJ.
14.06.090
Height
of
structures
(Rl-tO).
14.06.
tOO
Daylight plane
(Rl-lO).
14.06.110
Basements (R1-10).
14.06.120
Accessory structures, outdoor
barbeques and swimming pools
(R1-to).
14.06.130
Design control
(Rl-lO).
14.06.140
Off-street
parking
(Rl-lO).
14.06.150 Signs
(Rl-lO).
14.06.160
Fences (R1-10).
14.06.170
Nonconforming use regulations
(RI-
10).
14.06.010 R1-10
District.
The regulations, general provisions,
and
excep-
tions set forth in this
chapter
and
in
Chapt
er 14.66
shall apply in the
RI-
IO
Di
strict, which shall in-
elude:
A.
Mo
st properties in the general pl
an
desig-
nated Residential 2 - Single-Family;
B.
Resi
dent
ial 3 - Single-family small lot.
Existing clusters
of
established s
ma
ll
l
ot
s from
four
thou
s
and
(4,000)
to
nine thousand
(9
,000)
s
quare
Feet
in the R 1-10 zon
in
g district have been
identilied in the cit
y'
s
adopted
general plan. Where
indicated, it is the
intent
of
these regulations to
allow for
additiona
l nexibility,
in
order
to
provide
for house designs
that
are usable,
proport
ional,
and
appropriate
to smaller lot
s;
and
S
lI
PP. No.
20
376
C.
The
following
sha
ll
app
ly
to
those
ar
eas
designated in the Los Altos
Ge
neral
Pl
an as Resi-
dential 3 - Single-Family Sma
ll
Lot:
I . Flag l
ot
s
are
not
permitted
;
and
2.
Combining
of
existing small l
ots
is
not
permitted
, as
it
is
not
con
sistent with the city's
intent to preserve existing s
maLl
lots. (Ord. 04-267
§ 2 (part»
14.06.020
Permitted uses
(Rl-tO).
The
following uses sha
ll
be permitted in the
Rl-IO
District:
A. Single-family residences, including ancil-
lary accessory
str
u
ct
ur
es;
B.
Second living units as provided in
Chapte
r
14.1
4
of
this title;
C.
Home
occupation
s;
D.
Agr
iculture
and
horticulture;
E.
Animals
as provided in
Chapter
5.
10
of
this code;
and
F.
Sma
ll
family day
care
. (Ord. 05-285 § 2
(part):
Ord.
04-267 § 2
(part)
14.06.030 Conditional uses (R
1-1
OJ.
Upon
the
granting
of
a use
permit
in
acco
r-
dance with the provisions
of
Ch
apter
14.80
of
this
title, the following uses shall be
permitted
in the
R
I-I
0 Dis
tr
ict:
A. Flag l
ot
s;
B.
Large family day
care
;
and
C. Pre-existing
community
Faci
lities as pro-
vided in Ch
apter
14
.70 of this title. New
commu-
nity Facilities arc prohibited. (Ord. 05-285 § 2 (part):
Ord. 05-271 § 2 (part):
Ord.
04-267 § 2 (part»
14.06.040
Site
area
(R
1-1O).
The
minimum site
area
shall be ten
thousand
(
10
,000) sq u
are
feet, except th
at
on
corner
lots the
minimum site
ar
ea shall be eleven thousand
(II
,
OOO)
square
feet
and
on
nag
lot
s the minimum site area
shall be fifteen th
ou
s
and
(15,000) s
quar
e feel. (Ord.
04-267
§ 2
(part))
14.0
6.
050
Site frontage, width and d
efl
th
(R
t -I
O)
.
A.
Th
e
minimum
s
it
e fro
nta
ge ancl width shall
be eig
ht
y
(8
0) feet a
ncl
th
e
minimum
site de
pth
sha
ll
be one
hund
red (100) feet, except that
th
e
minimum
site w
idth
for a
co
rner
lot
sha
ll
be nin
ety
(90) f
ee
t
an
d the
minimum
site front
age
on a cul-
de-sac t
urn
a
round
sha
ll
be sixty (60) f
ee
t.
B.
Th
e
minimum
width
of
th
e access corridor
for
eac
h
fl
ag
lot sha
ll
be
twe
nt
y (20) feet,
an
d shall
access
dir
ec
tly
to
a
public
or priv
at
e s
tr
ee
t.
Th
e
access
cor
rido r sha
ll
not
co
nn
ect to any p
or
tion of
th
e
turna
ro
und space
of
a cul-de-
sac
. (
Ord
. 04-267
§ 2 (part»
14.06.060
C
ov
erage (
Rl
-10).
A. The
ma
x
imum
co
verage for all s
tru
c
tur
es
in excess of six feet in heig
ht
shall be
thir
ty-
fi
ve
(35)
perc
e
nt
of
th
e t
ota
l
ar
ea
of
the site where the
heig
ht
of one-st
ory
develo
pm
e
nt
d
oes
not exceed
twenty
(20)
fe
et.
B.
Th
e
ma
x
imum
co
ve
ra
ge for all s
tru
c
tur
es
in excess
of
six
fe
et in heig
ht
sha
ll
be
thirt
y (30)
perc
ent
on sites
where
the heig
ht
of
on
e-s
tory
develo
pm
e
nt
exceeds
tw
e
nt
y (20) f
ee
t
or
is devel-
oped with a two-
sto
ry
st
ru
ct
ure.
C.
On
sites where the lot cov
erag
e exceeds
thir
ty (30) perce
nt
, two-story s
tru
ct
ures sha
ll
not
be allowed.
(
Ord.
04-267 § 2
(part)
14.06.070
Floor
ar
ea
ratio (
RI-I
O).
A. F
or
lots with a net site
ar
ea
not
ex
cee
din
g
eleven thous
and
(
11
,000) s
quar
e feet,
th
e
ma
xi-
mum
floor a
rea
shall be
thir
ty-fi
ve
(35) percent
of
the net lot
area.
B.
Fo
rl
ots with a net site area exceeding eleven
tho us
and
(
11
,000) s
quar
e feet, the max
imum
floor
ar
ea
sha
ll
be t
hr
ee
thou
sand eig
ht
hund
red fift y
(3
,850) square feet plus ten (10)
pe
rcent times
th
e
net lot area minus eleven thous
and
(1
1,000) s
qu
are
feel.
(
Or
d. 04-267 § 2
(pa
r
t»
14.06.080
Se
tba
c
ks
(R \-1 0).
A. Except as noted below, the
minimum
set-
backs sha
ll
be as fo llows:
3
77
14.06.080
Fr
o
nt
25 feet
Int
e
ri
or si
de
First s
tor
y
10
f
ee
t
Seco
nd
story
17.5 feet
Exte
ri
or side 20 feet
,
Rea
r
25 feet
B.
A
minimum
of fifty (50) per
ce
nt of
the
re
quir
ed
front
yard area sha
ll
be perviou
s.
C.
Th
e second story se
tb
ack sha
ll
be mea-
sured from
th
e wall of the second story,
or
in
the
case
of
a sl
op
ing
ce
iling or r
oof
where
ther
e is
no
exte
ri
or wall, from
th
e
point
the sec
ond
story
ce
iling
ha
s a height of
fiv
e f
ee
t
or
gre
at
er from
th
e
finished
fl
oo
r.
D.
On
flag l
ot
s,
th
e
minimum
width of side
y
ard
s shall be fift
ee
n
(1
5) feel.
E.
On
a lot less than eig
ht
y (80) feet in
wi
dth,
or
in the case
of
a
co
rner
lot less than ninety (90)
fe
et in w
idth
(hereina fter refe
rr
ed to
as
"na
rr
ow"
lots),
th
e
minimum
width
of
s
id
e yards shall be as
follows:
I.
On
a na
rr
ow
co
rner l
ot
, the
minimum
w
idth
of
the side yard
adjoining
the s
tr
e
et
sha
ll
be twenty
(20) per
ce
nt
of the a
ve
ra
ge lot width
but
in no
case
less
than
ten (10) feet, whichev
er
is greate
r.
The
minimum
interior side y
ard
se
tback
for
corn
er lots
gr
ea
ter
than
eighty (80) feet in
width
shall be as
provided in s
ub
s
ection
A
of
this sectio
n.
Th
e
min-
imum
int
e
ri
or side ya rd
set
b
ack
for
co
rner lots less
tban eig
ht
y (80) f
ee
t in w
idth
shall be as
pro
vided
in s
ub
section (E)(2) of this section. For a
gara
ge
or
c
arp
o
rt
f
ac
ing an
exte
ri
or side y
ard
, the
minimum
setb
ac
k
to
the face of the s
tru
c
tur
e sha
ll
be twe
nty
(20) feet.
2.
Th
e
minimum
w
idth
of all
ot
her side ya rds
011 narrow lots sha
ll
be ten (10) perce
nt
of
th
e
average lot w
idth
b
ut
in no case less than
fi
ve f
ee
t,
whichever is greater,
fo
r
an
y portion
of
a s
tru
ct
ur
e
which is one s
tor
y
in
height, w
ith
seven and
on
e-
half feet
added
for
any
por
ti
on
of
a s
tru
ct
ur
e
which is two
st
ories in heig
ht
, except the
addi
-
ti
onal second s
tor
y
set
back may be r
ed
uced to live
feet if a t
hirt
y-
fi
ve (35) foot front ya rd set
ba
ck
is
pr
ovided.
Su
p
p.
No.:20
14.06.080
3.
No
t
wi
thstanding the provisions
of
Section
14.66.220 of tbis titl
e,
projections
in
to
the side
yards
of
narrow
lots shall not be
permitted,
with
the excepti
on
of
chimneys,
wh
ich shall
not
extend
more
than
two feet
into
the required si
de
yard
setba
ck,
and
roof
eaves, w
hi
ch shall
not
extend
more
than
eighteen
(1
8)
i
nch
es into
th
e req uired
s
id
e
ya
rd setback.
F.
On
a l
ot
less than one hundred (100) feet in
depth
, the rear yard shall be twenty-five (25) per-
cent
of
the
dep
th
of
the site or twenty (20) feet,
whichever is greater.
G. When a
str
u
ct
ure legally
const
ru
cted ac-
cording
to
existing yard
and
setback regulations
at
the time of cons
tru
c
ti
on encr
oac
hes upon cur-
rently required setbacks, the city plann
er
may ap-
prove
one
encroaching setback
to
be extended by
no
mor
e
than
twenty (20) fe
et
or
fi
fty (50) percen
t,
w
hi
chever is less, along its
ex
isting building
li
ne
witho
ut
a
va
ri
ance, subject
to
the following provi-
SIO
n
s:
I.
The
extension may only be applied
to
the
first s
tor
y;
2.
Only one such
ad
ministrati
ve
extension may
be permitted for the
li
fe
of
the building.
Other
extensi
ons
may be considered, subject
to
the filing
of
a variance application;
3. Extensions are o
nl
y pe
rmitt
ed for the
main
structure
and
canno
t result in a f
urth
er encroach-
ment
into
any required se
tback
area.
H. With the exce
ption
of
the provisions
of
Secti
on
14
.66.080
of
this title, when a s
tructure
has
an
existing
nonconforming
setbac
k
and
fi
fty
(50) pe
rc
e
nt
or
mor
e
of
the
fl
oo
r area of th
at
s
tructure
is
volu
nt
ar
il
y being eliminated or re-
placed, the entire stru
cture
sha
ll
be
brought
into
conformance with curr
ent
setback requirements.
(A mended during 2/06 suppleme
nt
; Ord. 05-285
§ 2 (part
);
Ord. 05-278 § I (part):
Ord.
04-267 § 2
(part»
(Ord.
No. 20 12-375, § 4, 1-24-2012)
14.06.090
Height
of
structures (R
1-1
0).
No
s
tr
ucture shall exceed t
wo
stories or twenty-
seven (27) feet in height from the n
at
ural grad
e.
On
SIIPP
.
No.
20
378
flag lots the height
of
st
ruct
ur
es shall be limited to
one
story a
nd
twenty (20)
fee
t in height. Base-
ments
sha
ll
not
be
cons
idered a stor
y.
When the l
ot
coverage exceeds
or
is
propo
sed
to
exceed thirty
(3
0) perce
nt
, the
maximum
height of s
tru
ct
ures
shall be twenty
(20) feet. (Ord. 04-267 § 2 (part))
14.06.100 Daylight plane
(Rl-lO).
No
st
ructure shall extend above
or
beyond a
daylight plane as
fo
llows:
A. For lots seve
nt
y (70) feet
or
great
er
in
wi
dt
h, the daylight pl
ane
starts at a heig
ht
of
eleven (I I) feet
at
each
side
property
li
ne and
at
an
angle
of
twenty-five (25) degrees from the horizon-
tal;
B.
On a l
ot
, w
hi
ch is less seventy (70) feet in
width
lo r its entire length, the plane st
arts
at
a
height
of
nineteen (19) feet
at
eac
h second
story
se
tb
ack line
and
proceeds inward
at
an
ang
le
of
twenty-five (25) degrees;
C. On a
si
te w
her
e the
gr
ad
e slopes greater
than
ten (10) pe
rc
e
nt
from s
id
e pr
operty
line to
side
property
line, the daylight plane
at
the lower
side
property
l
in
e sha
ll
be meas
ur
ed from a
point
equal to the average elevation
of
the site
and
pro-
ceed inward
at
an angle
of
twenty-five (25) de-
grees;
D.
An
extension of
an
ex
isting gab
le
roof
may project over or beyond the daylight plane
when it is determined by the city pl
anne
r that such
projec
ti
on is necessary to
maintain
the architec-
tural integrity
of
the s
tru
c
tur
e;
E. Televisi
on
and
radio antennas, chimneys,
and
other similar a
ppurt
enances may project above
the daylight pl
ane
as provided f
or
in Section
14.66.250. (Ord. 07-312 § 5 (part);
Ord.
04-267 § 2
(
part
»
14.
06.1l0
Basements
(Rl-lO).
Ba
sements sha
ll
be regulated as follows:
A. Basements shall
not
ex
tend beyond the
footprint
of
the main
or
accessory stru
ct
ure above;
B.
Light
wells, ingress and egress we
ll
s,
patio
we
ll
s,
and
ot
her simila r elements sha
ll
not be per-
mitted
wi
thin a required front or exterior
si
de yard
setback
.
The
se elements
may
be permitted within
an
interior
side
or
rear yard se
tback
, but in no
eve
nt
closer
than
five feet
to
a
property
line;
C.
Light
we
ll
s,
ingress
and
egress we
ll
s,
patio
wells,
and
other
similar el
ements
shall utilize ver-
tical r
eta
ining walls.
Co
ntour
graded slopes, which
expose the
ba
se
ment
as
a
sto
ry, are prohibited.
(Ord.
04-267 § 2 (part»
(Ord. No.
10
-348, § 3, 4-13-2010)
14.06.120 Accessory structures, outdoor
barbeques and swimming pools
(RI-lO).
A. Accessory s
tructure
s
that
are
no
mor
e
than
six feet in heig
ht
may be located in interior
and
exterior side
and
rear yard se
tbacks
subject
to
the
following provision
s:
I.
Themaximum
width
of
the accessory struc-
ture
shall be five feet.
2.
The
maximum length
of
the accessory struc-
ture shall be sixteen (16) feet.
3.
The
accessory
structure
shall be screened
from off-site view with solid fencing which is
not
lower in height
than
the
acc
essory
str
u
ct
u
re
and
which is
constructed
in
conformance
with the pro-
visions
of
Chapter
14.72
of
this title.
4. In
no
case shall there be less
than
a five-
foot
clearance
between
either
the accessory struc-
ture
and
th
e
main
s
tructure
or
the accessory struc-
tur
e
and
the
property
line.
B.
Accessory s
tructur
es
that
are
mor
e
than
s
ix
feet in heig
ht
may be loc
ate
d in the required
rear yard
setback
area
or
in the
main
structure's
building envelope, subject to the following provi-
SIO
n
s:
I.
Accessory s
tructure
s shall ha
ve
a mini-
mum setback
of
two
and
one-ha
lf
feet from the
side
property
line
and
a
minimum
setback from
the rear
property
line as foll ows:
i. Two
and
one-
half
feet when the
st
ruc
tur
e is
under ei
ght
feet in height;
ii. F
iv
e feet when the s
tru
cture is between
eight
and
len (10) feet in height;
379
14
.06.120
iii. Seven
and
one-ha
lf
feet when the struc-
ture
is
between ten (10)
and
twel
ve
(12) f
eet
in
height;
and
iv. Two
and
one-
half
feet when the rea r prop-
erty line abuts an a
ll
ey.
2.
No
p
ort
ion
of
any accessory s
tru
c
tur
e shall
project above a daylight plane, beginning
at
a
heig
ht
of
s
ix
feet
at
the side
property
line
and
increasing
at
a slope
of
four feet for each ten
(J
0)
f
eet
of
distance from the s
id
e
property
line
to
a
distance
of
ten (
10
) feet from the side
prop
er
ty
line.
3.
The
maximum a
ll
owable height for acces-
so
ry
s
tructur
es shall be twel
ve
(12) feet.
4.
The
maximum
a
ll
owable size for
eac
h ac-
cessory
structure
located in the required rear yard
setbac
k area shall be eight
hundred
(800) s
quare
feet
of
gross
noor
area.
5.
Notwithstanding
the provisions
of
Section
14.6<\2.10
of
this title,
no
portion
of
an accessory
structure, including
but
not
limited
to
roof
eaves,
c
himn
eys
and
vents, sha
ll
project
into
any re-
quir
ed setback
or
da
y
li
ght plane as
outlin
ed in this
subsection
B.
6.
The
architectural
and
site review
comm
it-
tee may approve
an
accessory
struc
tur
e located
entirely within the
main
str
u
ct
ure's building enve-
l
ope
to
extend up
to
e
ight
een (18) feet in heig
ht
if
the co
mmitt
ee finds
and
determines that the
addi-
tional height is necessary
in
order
to
estab
li
sh
architec
tur
al
compatib
ility with the
main
st
ruc-
ture.
C.
Outdoor
barb
eques, fireplace
s,
si
nk
s
and
si
milar structures located within the required rear
ya
rd setba
ck
shall be set back a minimum
of
fi
ve
feet from any
property
line. Said s
tructur
es shall
not be located in the required front
or
side yard
se
tb
ack
areas.
D.
Swimming pool
s,
hot tubs,
and
spas lo-
cated within the required rear
ya
rd
set
ba
ck shall
be set
back
a minimum
of"
five
feet from any
property
lin
e.
Said s
tru
ct
ur
es sha
ll
not
be located
in the required fr
on
t
or
side
yar
d setback
ar
ea
.
E.
Accessory struct
ur
es containing swimming
pool
motors
and
equ
ipm
ent
sha
ll
not
be located in
Supp. No.
20
14
.06. 1
20
a required interior s
id
e yard setback area. (Ord.
08-329 § 2 (part): Ord. 05-
285
§ 3 (part): Ord.
04-267 § 2 (part»
(O
rd
. No. 10-34
8,
§
2,
4-13
-2
010; Ord. No. 2012-
375,
§
3,
1-24-201
2)
14.06.130 Design control
(R
l -lO).
As provided
in
C
hapt
er
14.
76
or
this title.
(Ord. 04-
267
§ 2 (part»
14.06.t40
Off
-street parking (R1-10).
As prov
id
ed
in
Chapter 14.74
of
this title.
(Ord. 04-267 § 2 (part»
14.06.150 Signs
(R
l-lO).
As
provided in C
hapt
er
11
.04
of
this code.
(Ord.
04
-2
67
§ 2 (pa
rt»
14.06.160 Fences
CR
t-t
O).
As prov
id
ed
in
Chapter J 4.72
of
thi
~
title.
(Ord. 04-267 § 2 (part»
14.06.170
No
nconforming usc regulations
(Rt-tO).
As prov
id
ed
in
Chapter 14.66
of
this titl
e.
(Ord. 04-267 § 2 (par
t»
Supp. No. 20
380
