Table of Contents
1. Requirements for Jurisdictions
2. Sample Fill-in-the-blank Wall Section
3. Foundation Detail 4 ft -
4. Foundation Detail 4 ft +
5. Foundation Bolt and Protection Requirements
6. Garage / Carport Section Detail
7. Garage / Carport Section Detail
8. Sample Plan Format
9. Typical Wall, Floor, and Roof Framing
10. Framing Around Openings
11. Notching or Boring Plates and Studs
12. Typical Wall Framing Details
13. I-Joist Warnings
14. Guardrails and Stairway Requirements
15. Spiral and Winding Stairways
16. Windows in Basements and Sleeping Rooms
NOTICE: Information contained within this booklet is meant to comply
with the 2012 International Residential Code requirements. Appropriate
section numbers are provided for reference. This booklet is to be used as
an aid for Builders only, and does not supersede any applicable Codes or
Local Authority.
1
This booklet is to be used as an aid for the structural
and life safety portions in the building of one and two
family residential dwellings only! It does not cover any
commercial applications. Other methods and local
standard practices will continue to be accepted, but you
should discuss them with the Planning & Zoning
Department first. For more information please contact
Boise County Planning & Zoning Office at (208) 392-
2293.
AREAS OF REQUIRED
BOISE COUNTY FROST* WIND SPEED**
Idaho City 36” 90 MPH
Crouch 36” 90 MPH
Horseshoe Bend 36” 90 MPH
Placerville 36” 90 MPH
Centerville 36” 90 MPH
Gardena 36” 90 MPH
Garden Valley 36” 90 MPH
Grand Jean 36” 90 MPH
Lowman 36” 90 MPH
Pioneerville 36” 90 MPH
* Frost depth below finish ground level in inches
**Basic Wind Speeds Figure R301.2(4)A
2
Fill-in-the-blank Wall Section Detail
Pre Engineered Trusses by_______________________ ____x 12 Pitch
Roofing Type_________________________
Sheathing Size_________________
________R______Ceiling
Insulation
(2) 2x____ Top Plates
2x____ Header Typical
Diagonal Wall Brace @ Corners and
Every 25’ O/C. R-602.10.1
_________________________Window Mfg.
__________Style ____U-Value
Exterior Siding__________
_____________Gypsum Board
Sub-Sheathing__________
__________R_______Wall Insulation
2x____ Wall Studs________
@ _____O/C Floor Sheathing__________________
Floor Joists_________________
Ground to Wood 6” Min.--------
Redwood or Treated Sill Plate Required
2% Ground Slope From 1/2’ x 10” Anchor Bolts @ 6’ O/C. Min. R-403.1.6
Dwelling
____________” Thick Concrete Wall
Damp Proofing _____#______Rebar @______” O/C. Horiz.
Required________________ #______Rebar @______” O/C. Vert.
_____x_____Footing*
6”x12” Min. One Story 4” Floor
8”x15” Min. Two Story______
(2) #4 Rebar Continuous
TABLE R-403.1 Undisturbed or 95% Compacted Soil
* REFER TO PAGE #1 FOR REQUIRED FROST DEPTH
3
LESS THAN 4’ FOUNDATION
REDWOOD or TREATED SILL PLATE
W/ 1/2” x 10” ANCHOR BOLT @ 6’ o/c
R-403.1.6
Figure FOUNDATION WALL
R-403.1(3)
8” Min.
FINISH
GRADE WALL WIDTH MINIMUM
2 % SLOPE 6” ONE STORY
R-403.3 8” TWO STORY
R-403.1(1)
REINFORCEMENT
FROST # 4 BAR @ 48” o/c VERTICAL
36” MIN.* # 4 BAR @ 24” o/c HORIZONTAL
(1) # 4 BAR CONTINUOUS
6” ONE STORY
8” TWO STORY
Table R-403.1
MINIMUMS
12” ONE STORY
15” TWO STORY
Table R-403.1
* REFER TO PAGE #1 FOR REQUIRED FROST DEPTH
4
MORE THAN 4’ FOUNDATION
REDWOOD or TREATED SILL PLATE
W/ 1/2” x 10” ANCHOR BOLT @ 6’ o/c
R-403.1.6
FINISH 8” Min. CONCRETE WALL
GRADE
2% SLOPE WALLS OVER 9’ SHALL
R-401.3 BE ENGINEERED R-404.1.1
8” MINIMUM
FROST
36” Min.* FOR 8’ WALL & 6’ MAX. BACKFILL
( Pg. 2 ) REINFORCEMENT
#4 BAR @ 24” o/c VERTICAL
#4 BAR @ 24” o/c HORIZONTAL
LAP BARS 15” Min.
KEYWAY RECOMMENDED
(2) # 4 BAR
CONTINUOUS
8” Min. FOOTING
One Story 1500 psf
16” Min. Table R-403.1
NOTE: Unless otherwise approved by the Building Inspector, foundation
walls enclosing a basement below finished grade, shall be damproofed
outside by approved methods and materials. R-406
5
FOUNDATION BOLT AND REBAR
PROTECTION REQUIREMENTS
CLEARANCE TO REBAR
R-403.1.3
1 - 1/2” Min.
# 5 and smaller
when exposed 3/4” Min.
to weather # 11 and smaller when
or ground not exposed to weather
or in contact with ground
CAST-IN PLACE FORMED NOTE: FOR MASONRY
AGAINST EARTH WALL or REINFORCEMENT SEE
FOOTING LOCAL JURISDICTION.
TRENCHED
FOOTING
3” Min. 3” Min.
#5 or <
3” Min 1 - 1/2” Min. WITHIN 12 INCHES
OF EACH END
OF BOARD
2”X2”X3/16” PLATE WASHERS
SHALL BE USED IN SEISMIC
ZONES D1 & HIGHER 6’ o/c Max.
SEE PAGE 2 FOR ZONES
REDWOOD or
TREATED SILL PLATE
MINIMUM OF TWO (2)
1/2” ANCHOR BOLTS
PER PLATE + @ 6’ o/c
7” Min. EMBEDMENT
IN CONCRETE w/ WASHERS
R-403.1.6
UNDERFLOOR
ACCESS
18”x 24” Min.
R-408.4
FOUNDATION BOLT REQUIREMENTS
R-403.1
6
TYPICAL GARAGE WALL &
CARPORT SECTION DETAIL
12
ASTM D225 ASPHALT SHINGLES 4
w/ (2) LAYERS 15# FELT
R-905
1/2” OSB w/ H clips PRE ENGINEERED
TRUSS typ of 15
DOUBLE 2x4 2x4 STUDS @ 16” o/c
TOP PLATES
5/8” TYPE X
DIAGONAL WALL GYPSUM FIRE TAPED
BRACES @ CORNERS BETWEEN GARAGE
AND EVERY 25’ o/c AND DWELLING
Table R302.6
5/8” T-1-11
SIDING
2x4 REDWOOD SILL 4” CONC. SLAB w/ 4” CRUSHED
w/1/2”x10” A.B. @ 6’ o/c GRAVEL BASE UNDER
8”
MONOLITHIC 6” FORMED CONC. FOUND.
CONC. FOUND.
36” *
6” 1/2” OSB
BRICK w/ 1”
airspace
12” 12”
4”
NOTE: FOR SINGLE STORY ONLY.
FOR INSULATION AND FROST 36” *
REQUIREMENTS, PLEASE 8”
CONTACT THE LOCAL JURISDICTION
* SEE PAGE #1 FOR LOCAL FROST DEPTH 16”
7
Figure R602.10.6.2
8
‘ Y ‘ ‘ X ‘
1
NEW ADDITION
WINDOW TYPE
EXISTING HOUSE
STREET NAME
SITE PLAN ELEVATION VIEW
SCALE SCALE
‘X’
1 NOTE:
1. IDENTIFY THE SIZE OF
ALL FRAMING MEMBERS
2. SHOW ALL VERTICAL &
ROOF HORIZ. DIMENSIONS
FRAMING ‘Y’
MEMBERS ADDITION EXISTING 3. CLEARLY LABEL ALL
(TYPE/o.c.) SETBACK DIMENSIONS
‘Y’ NEW ADDITION ON SITE PLANS
‘Y’
4. MIN. DWG. SIZE 18”x 24”
‘Y’
BEAM SIZE
EXISTING HOME
TYPICAL PLAN FORMAT
FRAMING / FLOOR PLAN
1
CROSS SECTION OWNERS NAME / LOCATION
SCALE SCALE SCALE / DATE / DRAWN BY
9
TYPICAL WALL, FLOOR AND ROOF
FRAMING DETAIL
THIS FIGURE IS FOR ILLUSTRATION PURPOSES ONLY AND
THE WRITTEN TEXT SHALL APPLY ! FOR DIMENSIONAL WOOD ONLY !
* RAFTERS AND CEILING JOISTS
OR
APPROVED TRUSSED RAFTERS
DOUBLE PLATE
SECOND STORY
Table R602.3(5)
7’-6” Min. BEARING WALL;
CEILING Ht. ** Y MUST NOT EXCEED X
Over 10’ Engineered
NAILED TO STUD
1½” Min. BEARING X**
3” Min. LAP Y** 1x4 RIBBON CUT
@ SPLICE INTO STUD R502.6
R502.6.1
FIRE BLOCKING
BLOCKING AND BRIDGING R602.8
R502.7 MAIN FLOOR
3/4” Min. SUBFLOOR
FOR GIRDER SIZE
X** BLOCKING JOIST SEE R502.5(1)
Y** 2” TREATED BEAM
OR RW SILL
18” & 12” Min. CLEARANCE
GROUND
CONCRETE WALL MONOLITHIC
Figure R602.3(1)
10
FRAMING AROUND OPENINGS
R502.10 (FLOOR) R802.9 (CEILING)
FIREPLACE
BEARING WALL
2” CLEARANCE
RIM JOIST OR BLOCKING @ BEARING
DOUBLE TRIMMER JOISTS
1½” Min. DOUBLE HEADERS
BEARING > 4’
TAIL JOIST
DOUBLE JOISTS UNDER BEARING PARTITIONS
BLOCKING @ 4’ o/c Max.
DOUBLE TRIMMERS & HEADERS WHEN SPAN EXCEEDS 4 FEET
APPROVED FRAMING ANCHOR
APPROVED JOIST HANGER
DOUBLE
HEADER
HEADERS OVER 6 FEET TAIL JOISTS EXCEEDING 12 FEET
ILLUSTRATIONS FOR DIMENSIONAL WOOD ONLY!
11
GUIDE FOR CUTTING, NOTCHING & BORING
OF DIMENSIONAL WOOD JOISTS
Max. LENGTH = D/3* NO 2 HOLES OR NOTCHES PERMITTED
IN SAME CROSS-SECTION
D/6* Max.
JOIST *D = ACTUAL D/3* Max.
DIMENSION
D/4* Max. @ END 2” Min.
OUTER 1/3 of SPAN MIDDLE 1/3 of SPAN OUTER 1/3 of SPAN
NOTCHING NOT PERMITED
IN MIDDLE 1/3 OF SPAN
JOIST SIZE MAX. HOLE MAX. NOTCH DEPTH MAX. END NOTCH
2x4 NONE NONE NONE
2x6 1- 1/2” 7/8” 1- 3/8”
2x8 2- 3/8” 1- 1/4” 1- 7/8”
2x10 3” 1- 1/2” 2- 3/8”
2x12 3- 3/4” 1- 7/8” 2- 7/8”
GUIDE FOR NOTCHING AND BORING
OF DIMENSIONAL WOOD STUDS
5/8” Min.
25% IN EXTERIOR 40 % IN 40% IN 60% IN NONBEARING
OR BEARING WALLS NONBEARING ANY WALL OR DOUBLED STUDS, BUT
NOT MORE THAN TWO
SUCCESSIVE DOUBLED
STUDS AT A TIME
12
TYPICAL WALL FRAMING DETAILS
Figure R602.3(2)
1/8” x 1-1/2” METAL TIE ON EXTERIOR OR BEARING
OR EQUIVALENT R602.6.1 WALLS STAGER JOINTS 4’
R602.3.2
DOUBLE
APPROVED HEADER 2x PLATE
R502.5(1) / R502.5(2)
SINGLE 2x TRIMMER
OR MULTIPLE
FIRE STOP IF LOAD REQUIRES
AROUND STUD**
PIPE
SOLID BLOCKING
OR RIM JOIST
JOISTS
PROVIDE VENTS IN
ACCORDANCE WITH
R408.1 14” Min.
IN SHADED STUDS ANCHOR BOLTS w/
AREA TREATED WASHERS & NUTS
OR R W REQUIRED MAX 6’ OC
** MAXIMUM STUD SPACING
STUD SUPPORTING: 1 FLOOR + 2 FLOORS +
SIZE ROOF / CEILING ROOF / CEILING ROOF / CEILING NONBEARING
2x4 24” 16” NOT ALLOWED 24” up to 14’
2x6 24” 24” 16” 24” up to 20’
Maximum laterally unsupported stud height for bearing walls is 10’ unless permitted
by the Building Official, and justified by an analysis. See 602.3.1
BRACING SHALL MEET LOCAL SEISMIC AND WIND REQUIREMENTS !
Figure R602.3(5)
13
ENGINEERED I-JOIST WARNINGS
THESE CONDITIONS ARE NOT PERMITTED !
ALWAYS REFER TO MANUFACTURES INSTALLATION INSTRUCTIONS
REFER TO HOLE CHART * DO NOT OVERCUT HOLE DON’T USE HAMMER TO
FOR PERMITTED SIZING OR CUT INTO FLANGE ENLARGE HOLES OR
BEAT ON FLANGE
SIDE
VIEW
DO NOT DRILL OR DO NOT USE 16d NAILS DO NOT CUT BEYOND
DAMAGE FLANGE USE 8d, 10d & 12d NAILS ONLY INSIDE EDGE OF BEARING
STAY BACK 1-1/2” FROM END
DO NOT BIRDSMOUTH OR DO NOT NOTCH OR
DO NOT SUPPORT USE UNSUPPORTED DRILL ANY
JOIST ON WEB AS A TRUSS COMPONENT LAMINATED BEAM !
14
GUARDRAIL AND STAIRWAY
REQUIREMENTS
36” Min.
NOTE: ALL HANDRAILS
MUST RETURN TO WALL
AT ENDS AND SHALL 3-1/2”
BE BETWEEN 1-1/4” Max.
AND 2” IN
WIDTH 6’-8” Min. HANDRAIL
HEADROOM
1-1/2” Min.
34”-38”
OPEN RISERS
TREAD 10” Min. OPTIONAL
RISE TREAD OR RISE
4” Min. MAX. VARIATION 3/8”
7-3/4” Max.
7-3/4” Max. CABO
STAIRWAYS R311.7
4” SPHERE UNABLE TO PASS THROUGH
< 4”
36”
Min.*
34” Min. > 30”
36” Max.
6” SPHERE UNABLE
TO PASS THROUGH
APPROVED ALTERNATE
GUARDRAILS R312.1 HANDRAIL R311.7.8
NOTE: The above sections require that open sides of stairs with a total rise of
more than 30 inches above the floor or grade below must have a guardrail.
* The minimum required guardrail height for porches or balconies is 36”.
15
SPIRAL AND WINDING STAIRWAYS
- LESS THAN 10 OCCUPANTS
REQUIRED WIDTH OF RUN
SHALL BE PROVIDED AT THIS
LOCATION R311.7.10.1
6” Min.
6” Min.
6” Min. 12”
12”
POINTED STEPS
36” Min. NOT ALLOWED
36” Min.
ALTERNATE USE
WINDING STAIRWAY OF WINDERS
R311.7.10.1 R311.7.10
7-1/2” Min.
12”
26” Min.
1. MINIMUM HEADROOM 6’6”
2. 9-1/2” Max. RISE
BETWEEN TREADS
SPIRAL STAIRWAY
R311.7.10.1
16
EGRESS WINDOWS FOR BASEMENTS
AND SLEEPING ROOMS
R310
20” CLEAR Min.
OPENABLE OPENABLE
AREA 41” + AREA
5.7 sq ft 5.7 sq ft
MINIMUM MINIMUM
SLIDING WINDOW CASEMENT
34” +
20” CLEAR Min.
OPENABLE
AREA NOTE: FOR WINDOW WELL
5.7 sq ft 24” CLEAR REQUIREMENTS SEE THE
MINIMUM MINIMUM LOCAL JURISDICTION
SILL HEIGHT
DOUBLE OR 44” Max. FROM
SINGLE HUNG FINISH FLOOR
