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Detached ADU — 9526 Babauta Rd, San Diego CA 92129

9526 Babauta Rd, San Diego CA 92129

Detached ADUActiveRS-1-11
APN
3155610400
Subtype
Rear yard
Proposed SF
800 sf
Permit Count
0 permits
Scope of Work
New construction
Last Updated
Updated Jan 1
FoundationFraming & StructuralRoofingExterior EnvelopeInterior FinishAccessibilitySeismic / LateralMechanical / HVAC

What Framing & Structural requires

Permits & approvals required

No permit unique to this section — covered by the project's building permit (see Permits → Permit Requirements).

Review disciplines

  • Building / Structural reviewRequired
    Plan check for structural, life-safety, and CRC compliance.
    2022 California Residential Code (as amended by SDMC)

Submittal requirements

  • Deferred submittals (typical)Required
    Roof trusses, fire-sprinkler design (if required), solar PV, and MEP shop drawings are commonly approved as deferred submittals after permit issuance.
    City of San Diego Information Bulletin 400 — ADU/JADU Submittal
    From the code
    • lots that permit single-dwelling unit development but not multiple-dwelling unit development, detached ADU structures and ADUs attached to an existing accessory structure shall not exceed two stories. B. ADUs shall comply with the overall maximum structure height of the underlying base zone ... overlay zone. ADU Setback Regulations A. Conversions or Interior Alterations of Existing Structures Where an existing structure is converted to an ADU, the ADU may continue to observe the setbacks of the existing structure. B. Demolition and Reconstruction of Existing Structures Where an existing structure — SD Information Bulletin 400, p. 5
    • with environmentally sensitive lands is based on the allowable development area. The interior side yard and rear side yard setbacks for ADU structures over 16 feet in height that are adjacent to a residential use may use the base zone regulations if they are less ... than the ADU minimum 4-foot setback. C. 2025 ADU and JADU Regulation Amendments (O-21989) Adjustments to the ADU Home Density Bonus Program. Alignment with state law. Accessory Dwelling Unit (ADU) What is an ADU? An Accessory Dwelling Unit (ADU) is an attached — SD Information Bulletin 400, p. 2

Reference documents

Applicable documents — Structure / Framing & Structural · 5 · click to expand

RankTopics CoveredSection Citation
1
California Building Code 2022mandatory
California Code of Regulations Title 24, Part 2 — California Building Code
Framing & loads, Egress windows, Accessible routes
CBC §R310 — Emergency Escape and Rescue Openings
2
California Residential Code 2022mandatory
California Code of Regulations Title 24, Part 2.5 — California Residential Code
Foundation design, Framing & loads, Roofing assemblies, Interior wall finishes
CRC §R401 — Foundations
3
SD Information Bulletin 140advisory
City of San Diego Information Bulletin 140 — Residential Addition / Remodel
Additions, Remodels, Submittal requirements
SD Information Bulletin 140
4
SD Information Bulletin 205advisory
City of San Diego Information Bulletin 205 — Carports
Accessory Structures, Carports
SD Information Bulletin 205
5
SD Information Bulletin 211advisory
City of San Diego Information Bulletin 211 — Residential Decks
Decks, Structural
SD Information Bulletin 211

Reference tables (16)

Table 1 — Allowable Spans for DF #2 Roof Rafters (DF-Larch)

Table Capture v1.0

Dead Load: up to 10/20 (Shingles/Tiles) psf Total (incl. roofing); Live Load: 20 psf; L/Δ = 240; (T-R802.4.1(2))

Rafter SizeSpacingAllowable Span (Shingles / Tiles)
2X624"11'-11" / 10'-4"
2X616"14'-1" / 12'-7"
2X612"15'-6" / 14'-7"
2X824"15'-1" / 13'-0"
2X816"18'-5" / 16'-0"
2X812"20'-5" / 18'-5"
2X1024"18'-5" / 15'-11"
2X1016"22'-6" / 19'-6"
2X1012"26'-0" / 22'-6"
2X1224"21'-4" / 18'-6"
2X1216"26'-0" / 22'-7"
2X1212"26'-0" / 26'-0"
Source

Table 2 — Allowable Spans for DF #2 Ceiling Joist (DF-Larch)

Table Capture v1.0

Dead Load: 10 psf; Live Load: 20 psf (Light Storage); L/Δ = 240; (T-R802.5.1(2))

Joist SizeSpacingAllowable Span
2X424"7'-3"
2X416"8'-11"
2X412"9'-10"
2X624"10'-8"
2X616"13'-0"
2X612"15'-0"
2X824"13'-6"
2X816"16'-6"
2X812"19'-1"
2X1024"16'-5"
2X1016"20'-2"
2X1012"23'-3"
Source

Table 3 — Allowable Spans for DF #2 Floor Joist (DF-Larch)

Table Capture v1.0

Dead Load: 10 psf; Live Load: Floor 40 psf; L/Δ = 360; (T-R502.3.1(2))

Joist SizeSpacingAllowable Span
2X624"8'-3"
2X616"9'-9"
2X612"10'-9"
2X824"10'-5"
2X816"12'-9"
2X812"14'-2"
2X1024"12'-9"
2X1016"15'-7"
2X1012"18'-0"
2X1224"14'-9"
2X1216"18'-1"
2X1212"20'-11"
Source

Table 4 — Allowable Spans (Braced/Unbraced) for DF #2 Roof Beams & Headers, Exterior & Interior Bearing Walls (DF-Larch)

Table Capture v1.0

Max. Dead Load: 20 psf; Max Live Load: 20 psf; (T-R 602.7(1))

Size12-ft Bldg WidthNT24-ft Bldg WidthNT36-ft Bldg WidthNT
2-2x66'-0"/4'-3"14'-7"/3'-2"13'-10"/2'-8"1
2-2x87'-7"/5'-4"15'-9"/4'-0"24'-10"/3'-4"2
2-2x109'-0"/6'-9"16'-10"/4'-9"25'-9"/4'-4"2
2-2x1210'-7"/7'-5"28'-1"/5'-8"26'-10"/4'-9"2
3-2x89'-5"/6'-7"17'-3"/5'-1"16'-1"/4'-3"2
3-2x1011'-3"/7'-10"28'-7"/6'-2"27'-3"/5'-1"2
3-2x1213'-2"/9'-3"210'-8"/7'-1"28'-6"/6'-0"2
4-2x810'-11"/7'-8"28'-4"/5'-10"27'-0"/5'-0"2
4-2x1012'-11"/9'-0"29'-11"/7'-0"28'-4"/5'-10"2
4-2x1215'-3"/10'-8"211'-8"/8'-2"29'-10"/6'-9"2

a. Building width is perpendicular to ridge measured to exterior walls.

b. NT – Number of trimmer studs required to support each end of header.

d. Allowable span of braced beam / Allowable span of unbraced beam.

Source

Table 5 — Cantilever Spans for Floor Joists

Table Capture v1.0

Max. deck dead load 10 psf; Live load 40 psf

Size (DF-Larch #2)SpacingCantilever SpanUplift Force (lbs)
2x812"34"165
2x816"29"180
2x1012"49"201
2x1016"42"220
2x1024"34"255
2x1216"57"268
2x1224"47"330

a. Ratio of backspan to cantilever span shall be not less than 2:1.

b. A full-depth floor joist shall be provided at the cantilevered ends. Solid blocking shall be provided between joists over the support.

c. Connection angle capable of resisting the indicated uplift force shall be provided at the backspan support.

Source

Table 6 — Rafter Heel Connection to Ceiling Joist

Table Capture v1.0

Roof Live Load 20 psf [Table R802.5.2(1)]; Minimum number of 16d common nails

Rafter SlopeTie Spacing (in)Roof Span 12 ftRoof Span 20 ftRoof Span 28 ftRoof Span 36 ft
3:1216581013
3:12247111519
4:121646810
4:1224581215
5:12163568
5:122447912

Roof span is measured between exterior walls.

Source

Table 7 — Allowable Spans & Loads for Wood Structural Panel (Floor & Roof Sheathing)

Table Capture v1.0

Sheathing Grade STRUCT-1; continuous over two or more spans; strength axis perpendicular to supports; applies to panels 24" or wider; (T-R503.2.1.1(1))

Panel Span Rating (Roof/Floor)Min Panel Thickness (in)Roof Max Span — Edge SupportRoof Max Span — No Edge SupportRoof Total Load (psf)Roof Live Load (psf)Floor Max Span (in, T&G/blocking)
24/03/824204030
24/167/162424504016
32/1615/32, 1/23228403016
40/2019/32, 5/84032403020
48/2423/32, 3/44836453524
Source

Table 8 — Nailing Schedule

Table Capture v1.0

(T-R602.3(1))

ConnectionFasteningRemarks
Roof
Blocking between joists or rafters to top plate3-8d (2-1/2" x 0.113")Toe nail
Ceiling joist to plate3-8d (2-1/2" x 0.113")Toe nail
Ceiling joist not attached to parallel rafter, laps over partitions4-10d (3" x 0.128")Toe nail
Collar tie rafter, face nail or 20-gage ridge strap3-10d (3" x 0.128")Face nail
Rafter to plate2-16d (3-1/2" x 0.135")Toe nail
Roof rafters to ridge, valley or hip rafters4-16d (3-1/2" x 0.135") / 3-16d (3-1/2" x 0.135")Toe nail / End nail
Wall
Built-up corner studs10d (3" x 0.128")16" o.c.
Built-up header two pieces with ½" spacer16d (3.5" x 0.162")16" o.c. along each edge
Continued header two pieces16d (3.5" x 0.162")16" o.c. along each edge
Continuous header to stud4-8d (2-1/2" x 0.113")Toe nail
Double studs16d (3.5" x 0.128")12" o.c.
Double top plates10d (3" x 0.128")12" o.c. Face nail
Double top plates, minimum 24-inch offset of end joints, face nail in lapped area8-16d (3-1/2" x 0.135")Face nail
Sole plate to joist or blocking16d (3-1/2" x 0.135")12" o.c. Face nail
Sole plate to joist or blocking at braced wall panels3-16d (3-1/2" x 0.135")12" o.c. Face nail
Stud to sole plate4-8d (2-1/2" x 0.113") or 3-16d (3-1/2" x 0.135")Toe nail
Top or sole plate to stud3-16d (3-1/2" x 0.135")End nail
Top plates, lap at corners and intersections3-10d (3" x 0.128")Face nail
Floor
Joist to sill or girder4-8d (2-1/2" x 0.113")Toe nail
Rim joist to top plate (roof application also)8d (2-1/2" x 0.131")6" o.c. Toe nail
Built-up girders and beams, 2-inch lumber layers10d (3" x 0.128")Nail each layer: 24" o.c. at top and bottom, staggered; two nails at ends and at each splice
Ledger strip supporting joists or rafters4-16d (3-1/2" x 0.135")At each joist or rafter

1. When nails are clinched, nailing may be reduced by 25 percent.

Source

Table 9 — Title 24 Energy Requirements (Prescriptive) for Climate Zone 7 & 10

Table Capture v1.0

Prescriptive energy requirements (Climate Zones 7 & 10)

ComponentClimate ZoneRequirement
Insulation — CeilingClimate Zone 7R-30
Insulation — CeilingClimate Zone 10R-38 (Option B), R-30 (Option C)
Insulation — WallClimate Zone 7 & 10R-13 + R8 Cont.
Insulation — FloorClimate Zone 7 & 10R-19
Insulation — RoofClimate Zone 7 & 10Radiant barrier required in new roof
Fenestration — TypeDual Pane
Fenestration — Maximum Sq.Ft.20% of FA* totalUF 0.30 or lower
Fenestration — 5% West FacingSHGC 0.23 or lower
Doors — No GlazingUF 0.20 or lower
Doors — Glazing DoorTreated as fenestration

1. All buildings shall comply with the Quality Insulation Installation (QII) requirements in Table 150.1-A or B.

2. The area of any glass removed, as a direct result of the room addition, may be added to the 20% (*FA = floor area).

Source

Post Spacing - Rafter Span (Feet)

Table Capture v1.0
Post Spacing (Feet)68101214161820
41212121212121212
61212121212121214
81212121212141414
101212121414141616
121212141416161818
141212141616181820
161214141618182020
181214161818202022
201414161820202224

1

Source

Rafter Span - Rafter Spacing Center-to Center (Inches)

Table Capture v1.0
Rafter Span (Feet)12 5/16" plywood sheathing16 3/8" plywood sheathing24 1/2" plywood sheathing
62x42x42x4
72x42x42x4
82x42x42x6
92 x 42 x 62 x 6
102 x 62 x 62 x 6
112 x 62 x 62 x 6
122 x 62 x 62 x 6
132 x 62 x 62 x 8
142 x 62 x 62 x 8
152 x 62 x 82 x 8
162 x 82 x 82 x 10
172 x 82 x 82 x 10
182 x 82 x 82 x 10
192 x 82 x 102 x 12
202 x 82 x 102 x 12

1,2

Source

Post Spacing / Rafter Span (Feet)

Table Capture v1.0
(Feet)468101214161820
44 x 44 x 44 x 44 x 44 x 44 x 44 x 44 x 44 x 4
64 x 44 x 44 x 44 x 44 x 44 x 44 x 44 x 44 x 6
84 x 44 x 44 x 64 x 64 x 64 x 64 x 64 x 64 x 6
104 x 44 x 64 x 64 x 64 x 64 x 64 x 64 x 84 x 8
124 x 64 x 64 x 64 x 84 x 84 x 84 x 84 x 84 x 10
126 x 86 x 86 x 86 x 86 x 86 x 86 x 86 x 86 x 8
144 x 64 x 84 x 84 x 84 x 84 x 104 x 104 x 104 x 10
146 x 86 x 86 x 86 x 86 x 86 x 86 x 106 x 106 x 10
164 x 84 x 84 x 84 x 104 x 104 x 104 x 124 x 124 x 14
166 x 86 x 86 x 86 x 86 x 86 x 106 x 106 x 106 x 10
184 x 84 x 84 x 104 x 104 x 104 x 124 x 124 x 144 x 14
186 x 86 x 86 x 86 x 86 x 106 x 106 x 106 x 126 x 12
204 x 84 x 104 x 104 x 124 x 124 x 144 x 14
206 x 86 x 86 x 106 x 106 x 106 x 126 x 126 x 126 x 14

1,2

Source

Regulations SDMC Section

Table Capture v1.0
RegulationsSDMC Section
Residential Base Zones131.0401
Planned Districts151.0101
Brush Management142.0412
Landscape142.0401
Environmentally Sensitive Lands143.0101
Parking142.0501
Overlay Zones132.0120
Source

Table 1 - Spacing of Joists

Table Capture v1.0
SpeciesSize121624
Douglas fir-Larch #2 or Redwood #12x66-96-25-1
Douglas fir-Larch #2 or Redwood #12x88-107-106-6
Douglas fir-Larch #2 or Redwood #12x1011-29-77-10
Douglas fir-Larch #2 or Redwood #12x1212-911-29-1
Source

Table B - Cantilever Length for Deck Joists (ft. - in.) 1,2,5

Table Capture v1.3

Live Load= 60 psf, Dead load= 10 psf, L/△=240

SizeSpacing (inches)3,4 = 12Spacing (inches)3,4 = 16Spacing (inches)3,4 = 24
2x61-00-100-9
2x81-71-61-5
2x102-52-22-0
2x123-22-102-3

The maximum cantilever length shall also be limited to one-fourth of the joist span.

Joist spacing for diagonal decking shall not exceed 16 inches.

Cantilever span includes 220 lbs. point load applied to end.

Solid blocking shall be provided between joists over the support.

Source

Joist span less than or equal to:

Table Capture v1.0
SpeciesSize^56 ft.8 ft.10 ft.12 ft.14 ft.16 ft.18 ft.
Douglas Fir-Larch #2 Redwood #13 x 6 or 2- 2 x 63-93-33-0----
Douglas Fir-Larch #2 Redwood #13 x 8 or 2- 2 x 84-94-33-93-53-2--
Douglas Fir-Larch #2 Redwood #13 x 10 or 2- 2 x 105-105-24-74-33-103-73-4
Douglas Fir-Larch #2 Redwood #13 x 12 or 2- 2 x 126-105-115-34-104-64-34-0
Douglas Fir-Larch #2 Redwood #14 x 64-63-103-53-3---
Douglas Fir-Larch #2 Redwood #14 x 85-115-24-74-33-103-93-5
Douglas Fir-Larch #2 Redwood #14 x 107-06-25-44-104-64-33-10
Douglas Fir-Larch #2 Redwood #14 x 128-27-16-45-85-34-104-7
Douglas Fir-Larch #2 Redwood #13- 2 x 65-34-94-33-103-73-43-2
Douglas Fir-Larch #2 Redwood #13- 2 x 86-96-05-35-04-74-34-0
Douglas Fir-Larch #2 Redwood #13- 2 x 108-67-56-75-86-05-35-0
Douglas Fir-Larch #2 Redwood #13- 2 x 129-108-67-87-06-56-05-8

5

8

Source