City of Aurora
RESIDENTIAL DECKS SPAN CHART
Permit Center • 15151 E. Alameda Parkway, Ste 2400 • Aurora, CO 80012
Phone: 303.739.7420 • Fax: 303.739.7551 • Email: permitcounter@auroragov.org
DECK JOIST SPAN WITHOUT CANTILEVER
JOIST SIZE
JOIST SPACING
MAXIMUM SPAN
2’ X 6”
12” ON CENTER (OC)
9’ - 6” *(8’ - 10”)
16” OC 8’ - 8” *(8’ - 0”)
24” OC
7’ - 2” *(7’ - 10”)
12” OC
12’ - 6” *(11’ - 8”)
16” OC
11’ - 1” *(10’ - 7”)
24” OC
9’ - 1” *(8’ - 8”)
12” OC
15’ - 8” *(14’ - 11”)
16” OC
13’ - 7” *(13’ - 0”)
24” OC
11’ - 1” *(10’ - 7”)
12” OC
18’ - 0” *(17’ - 5”)
16” OC
15’ - 9” *(15’ - 1”)
24” OC
12’ - 10” *(12’ - 4”)
2” X 8”
2” X 10”
2” X 12”
Spans in this Table were derived from IRC Table R507.5. Design criteria: #2 Douglas fir-larch, Hem-fir, or Spruce-pine-fir
joists with live/dead load 40/10 psf. DOL 1.00; L / 360. Cantilevered spans not exceeding the nominal depth of the joist are
permitted. *(Redwood, Cedar, Ponderosa Pine, and Red Pine span lengths).
DECK JOIST SPAN WITH CANTILEVER
JOIST SIZE
JOIST SPACING
MAXIMUM SPAN
2’ X 6” 12” ON CENTER (OC) 6’ - 3” *(5’ - 7”)
16” OC 6’ - 3” *(5’ - 7”)
24” OC 6’ - 3” *(5’ - 7”)
12” OC
9’ - 5” *(8’ - 6”)
16” OC
9’ - 5” *(8’ - 6”)
24” OC
9’ - 1” *(8’ - 6”)
12” OC 13’ - 7” *(12’ - 3”)
16” OC
13’ - 7” *(12’ - 3”)
24” OC
11’ - 1” *(10’ - 7”)
12” OC 18’ - 0” *(16’ - 5”)
16” OC 15’ - 9” *(15 - 1”)
24” OC 12’ - 10” *(12’ - 4”)
2” X 8” 2” X 10”
2” X 12” Spans in this Table were derived from IRC Table R507.5. Design criteria: #2 Douglas fir-larch, Hem-fir, or Spruce-pine-fir
joists with live/dead load 40/10 psf. DOL 1.00. Cantilevered spans not exceeding one-fourth of the actual joist span are
permitted. L / 360 at main span, L / 180 at cantilever with a 220-pound point load applied to end.
*(Redwood, Cedar, Ponderosa Pine, and Red Pine span lengths).
Residential Decks Span Chart (Revised 05/2016)
DECK BEAM SPAN TABLE
BEAM SPAN BETWEEN SUPPORTS (SPACING OF POSTS)
BEAM SIZE
6 8 1012141618
2 - 2 X 6
5-5 4-8 4-2 3-10 3-6 3-1 2-9
2 - 2 X 8
6-10 5-11 5-4 4-10 4-6 4-1 3-8
2 - 2 X 10
8-4
7-3
6-6
5-11
5-6
5-1
4-8
2 - 2 X 12
9-8
9-5
7-6
6-10
6-4
5-11
5-7
4 X 6
6-5
5-6 4-11
4-6
4-2
3-11
3-8
4 X 8
8-5
7-3
6-6
5-11
5-6
5-2
4-10
4 X 10
9-11
8-7
7-8 7-0
6-6
6-1
5-8
4 X 12
11-5
9-11
8-10
8-1
7-6
7-0
6-7
3 - 2 X 6
7-4
6-8
6-0
5-6
5-1
4-9
4-6
3 - 2 X 8
9-8
8-6
7-7
6-11
6-5
6-0
5-8
3 - 2 X 10
12-0
10-5
9-4
8-6
7-10
7-4
6-11
3 - 2 X 12
13-11
12-1
10-9
9-10
9-1
8-6
8-1
Spans in this table were derived from IRC Table 507.6. Design Criteria: #2 Douglas fir-larch, Hem-fir, Spruce-pine-fir,
Redwood, Cedar, and Ponderosa Pine beams with live/dead load 40/10 psf. DOL 1.00; L/360 at main span and L/180 at
cantilever with a 220-pound point load applied at the end. Beam depth shall be greater than or equal to depth of the
joists with flush beam condition. Maximum cantilever one-fourth actual span permitted. Interpolation permitted.
DECK POST HEIGHT
DECK
MAXIMUM HEIGHT
4 X 4
8’
4 X 6
8’
6 X 6
14’
JOISTS
JOISTS
BEAM
BEAM
POST
POST
OPTIONAL
CANTILEVER
BEAM SPAN
DROPPED BEAM
OPTIONAL
OPTIONAL
CANTILEVER
CANTILEVER
BEAM SPAN
FLUSH BEAM
OPTIONAL
CANTILEVER
TABLE R507.4
MAXIMUM JOIST SPACING
MAXIMUM ON-CENTER JOIST SPACING
MATERIAL TYPE AND NOMINAL SIZE
Perpendicular to Joist
Diagonal to Joist
1¼ inch thick wood
16 inches
12 inches
2 inch thick wood
24 inches
16 inches
Plastic composite
In accordance with Section R507.3
In accordance with Section R507.3
For SI:-1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 degree = 0.01745 rad.
a. Maximum angle of 45 degrees from perpendicular for wood deck boards.
TABLE R507.2
DECK LEDGER CONNECTION TO BAND JOISTa,b
(Deck live load = 40 psf, deck dead load = 10 psf, snow load < 40 psf)
JOIST SPAN
CONNECTION DETAILS
6’ and less
6’1” to 8’
8’1” to 10’
10’1” to 12’
12’1” to 14’
14’1” to 16’
16’1” to 18’
ON-CENTER SPACING FASTENERS
½-inch diameter lag screw with ½-inch
maximum sheathingc,d
30
23
18
15
13
11
10
½-inch diameter bolt with ½-inch
maximum sheathingd
36
36
34
29
24
21
19
½-inch diameter bolt with 1-inch
maximum sheathinge
36
36
29
24
21
18
16
For SI: 1-inch = 25.4 mm, 1 foot = 304.8 mm, 1 pound per square foot = 0.0479 kPa.
a.Ledgers shall be flahsed in accordance with Section R703.8 to prevent water from contacting the house band joist.
b.Snow load shall not be assumed to act concurrently with live load.
c. The tip of the lag screw shall fully extend beyond the inside face of the band joist.
d.Sheathing shall be wood structural panel or solid sawn lumber.
e.Sheathing shall be permitted to be wood structural panel, gypsum board, fiberboard, lumber or foam sheathing. Up to
½-inch thickness of stacked washers shall be permitted to substitute for up to ½-inch of allowable sheating thickness
where combined with wood structural panel or lumber sheathing.
TABLE R507.2
DECK LEDGER CONNECTION TO BAND JOISTa,b
(Deck live load = 40 psf, deck dead load = 10 psf, snow load < 40 psf)
MINIMUM END AND EDGE DISTANCES AND SPACING BETWEEN ROWS
Ledger
a
TOP EDGE
BOTTOM EDGE
ENDS
2-inches
¾-inch
d
Band Joistc
ROW SPACING
¾-inch
b
2-inches
1⅝-inchesb
2-inch
2-inchesb
1⅝-inchesb
2”
MIN
For SI: 1-inch = 25.4 mm.
a.Lag screws or bolts shall be staggered from the top to the bottom along the horizontal run of the deck ledger in accordance
with Figure R507.2.2(1).
b.Maximum 5-inches.
c. For engineered rim joists, the manufacturer’s recommendations shall govern.
d.The minumum distance from bottom row of lag screws or bolts to the top edge of the ledger shall be accordance with
Figure R507.2.1(1).
STAGGER FASTENERS
IN 2 ROWS
5.5” MIN. FOR 2X8*
6.5” MIN. FOR 2X10
7.5” MIN. FOR 2X12
5” MAX
2” MIN
LEDGER
LAG SCREW OR BOLT
3/4” MIN.
*DISTANCE SHALL BE PERMITTED TO
BE REDUCED TO 4.5” IF LAG SCREWS
ARE USED OR BOLT SPACING IS
REDUCED TO THAT OF LAG SCREWS TO
ATTACH 2X8 LEDGERS TO 2X8 BAND
JOISTS
For SI: 1-inch = 25.4 mm.
FIGURE R507.2.1(1)
PLACEMENT OF LAG SCREWS AND BOLTS IN LEDGERS