Page 446 - 2018_IRC

ROOF-CEILING CONSTRUCTION

R804.3.2.1 Minimum roof rafter sizes. Roof rafter zontally. Outlookers at gable endwalls shall be
size and thickness shall be determined in accordance installed in accordance with Figure R804.3.2.1.2.
with the limits set forth in Table R804.3.2.1(1) based on R804.3.2.2 Roof rafter support brace. Where used to
the horizontal projection of the roof rafter span. For reduce roof rafter spans in determining roof rafter sizes,
determination of roof rafter sizes, reduction of roof a roof rafter support brace shall meet all of the follow-
spans shall be permitted where a roof rafter support ing conditions:
brace is installed in accordance with Section 1. Minimum 350S162-33 C-shaped brace member
R804.3.2.2. The reduced roof rafter span shall be taken with maximum length of 8 feet (2438 mm).
as the larger of the distances from the roof rafter support
brace to the ridge or to the heel measured horizontally. 2. Minimum brace member slope of 45 degrees
(0.785 rad) to the horizontal.
For the purpose of determining roof rafter sizes in
Table R804.3.2.1(1), ultimate design wind speeds shall 3. Minimum connection of brace to a roof rafter and
be converted to equivalent ground snow loads in accor- ceiling joist with four No.10 screws at each end.
dance with Table R804.3.2.1(2). Roof rafter sizes shall 4. Maximum 6 inches (152 mm) between brace/ceil-
be based on the higher of the ground snow load or the ing joist connection and load-bearing wall below.
equivalent snow load converted from the ultimate 5. Each roof rafter support brace greater than 4 feet
design wind speed.
(1219 mm) in length, shall be braced with a sup-
R804.3.2.1.1 Eave overhang. Eave overhangs shall plemental brace having a minimum size of
not exceed 24 inches (610 mm) measured horizon- 350S162-33 or 350T162-33 such that the maxi-
tally. mum unsupported length of the roof rafter support
R804.3.2.1.2 Rake overhangs. Rake overhangs brace is 4 feet (1219 mm). The supplemental brace
shall not exceed 12 inches (305 mm) measured hori- shall be continuous and shall be connected to each
roof rafter support brace using two No. 8 screws.

OPTION #1
1 FT MAX 1 FT MIN
#8 SCREWS
350S 162-33 BLOCKING #8 SCREWS @ 6 IN. O.C. @ 6 IN. O.C.
BETWEEN OUTLOOKERS
WITH #8 SCREWS @ 6 IN.
0.C. TO WALL TRACK
(MIN. 3 SCREWS EACH)
CLIP ANGLE
WITH 2 - #8
SCREWS EACH
LEG
ROOF RAFTER
4 - #8 SCREWS
(OUTLOOKER TO
WALL TRACK)
350S162-33 (WITH
WALL SHEATHING
0 WEB HOLES)
OUTLOOK RAFTERS
ALIGN WITH EACH
GABLE WALL STUD
GABLE
ENDWALL
STUDS OPTION #2
1 FT MAX 1FT MIN
(SEE NOTE)
#8 SCREWS @ 6 IN. O.C.

350S 162-33 OUTLOOKERS
@ 2 FT O.C. WITH
CONTINUOUS
TRACK EACH END
2 - #8 SCREWS
TO EACH STUD ROOF RAFTER

WALL SHEATHING
NOTE: ROOF SHEATHING JOINTS PARALLEL
TO THE GABLE ENDWALL ARE NOT PERMITTED
IN THIS REGION UNLESS AN APPROVED
GABLE
ENDWALL TENSION TIE IS PROVIDED.
STUDS
For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm.
FIGURE R804.3.2.1.2
GABLE ENDWALL OVERHANG DETAILS
2018 INTERNATIONAL RESIDENTIAL CODE ® 421
Copyrighted © 2017 by, or licensed to, ICC (ALL RIGHTS RESERVED); licensed to UL, LLC pursuant to License Agreement with ICC. No further reproductions authorized or distribution authorized.
ANY UNAUTHROIZED REPRODUCTION OR DISTRIBUTION IS A VIOLATION OF THE FEDERAL COPYRIGHT ACT AND THE LICENSE AGREEMENT; AND SUBJECT TO CIVIL AND CRIMINAL PENALTIES THEREUNDER.