Installation Guide

Figure 5: Certi-label Shingle Application
Figure 5a: Course Alignment
For 4:12 slope and steeper, use
Number 1 Grade shingles at 5",
5 1/2" and 7 1/2” exposures for
16", 18" and 24" shingles
respectively. For lower roof
slopes and lower product
grades use reduced exposures
(See Page 20)
Centerline of heart
GENERAL DESIGN AND APPLICATION DETAILS
Architect: Gaylord Grainger, Libby O’Brien-Smith Architects, Photo: Eduardo Calderon
Spaced sheathing should
be 1 x 4 or 1 x 6
Rafter
header
5
NEW PIC
Knot or
similar defect
1 1/2"
Product should project
1 1/2 beyond the fascia
and approximately 1"
over the gable or rake end
"
Fascia
Adjacent course joints
should be offset
1 1/2" minimum
Alternate course
joints should
not align
Gutter
Space shingles
1/4" - 3/8" apart
Two nails (only) for each
shingle approximately 3/4" from
edge and approximately 1 1/2”
above exposure line.
First course doubled or tripled
Solid wood sheathing
Eave protection (extend to rake edge)
Rafter
Certi-label Shingles
Certi-label Shingle Application
There are two acceptable methods for
application of spaced sheathing: One is to
space 1 x 4 boards to coincide with the
weather exposure (Table 2, Page 20) of the
shingles (Figure 5). Thus, if the shingles are to
be laid at 5 1/2" to the weather, the sheathing
boards would also be spaced at 5 1/2" on
center. In this method of application each
shingle is nailed to the center of the 1 x 4
board. With 7 1/2" weather exposures, the
center of the sheathing board shall equal the
distance of the weather exposure.
Alternatively, although not commonly used, a
permeable underlayment (i.e. breathable),
such as roofing felt, may be applied over
either solid or spaced sheathing.
Please note that the only solid sheathing
product tested for use with Certi-label shakes
and shingles is plywood. Check with your
local building official for plywood
thickness/dimensions.
Regardless of style, the following basic
application details (Figure 5) must be
observed.
1. Shingles must be doubled or tripled at all
eaves.
2. Butts of first course shingles should project
1 1/2" beyond the fascia and approximately
1" over the gable or rake end.
3. Spacing between adjacent shingles (joints)
should be a minimum of 1/4" and a
maximum of 3/8".
4. Certi-label shingles shall be laid with a side
lap not less than 1 1/2" between joints in
adjacent courses, and not more than 10%
shall be in direct alignment in alternate
courses. Check with your local building
official in your area.
5. In lesser grade shingles (Figure 5a)
containing both flat and vertical grain, joints
should not be aligned with centerline of
heart.
6. Flat grain shingles wider than 8" should be
split in two before nailing. Knots and similar
defects should be treated as the edge of the
shingle and the joint in the course above
placed 1 1/2" from the edge of the defect.