Installation Guide

SOLID DECK APPLICATION/HIGH HUMIDITY AREA DETAILS
19
Figure 23b: Vertical Strips Over Solid Sheathing Application
(Option 2 Depicted)
Figure 23c: Continuous Ventilation Product
(Option 4 Depicted)
Figures 23a - 23c: High Humidity Area Details
In areas of high humidity where
solid sheathing is required:
Following are 4 different suggested methods
of application to increase longevity:
1. Apply Certi-Last pressure-impregnated
treated shakes or shingles directly to the
sheathing. (Figure 23a)
2. Apply vertical strips over the sheathing in
alignment with the rafters below, then
place horizontal furring strips on top of
the vertical boards. (See Figure 23b).
3. Apply horizontal furring strips to the
deck, spaced at the exposure of the
product.
4. A continuous ventilation product may
be used beneath the Certi-label roofing
material (See Figure 23c).
Note: Good ventilation is essential.
Ridge and soffit vents are recommended.
4" overlap of felt
Continuous ventilation
product
24" Certi-label shakes
at 10" exposure
18" felt interlay
2 nails per shake
1 x 4 or 1 x 6
nailing strips
4" overlap of felt
2 x 4 spacers
Solid sheathing
Solid sheathing at eave
Shake
starter course
36" felt underlay
(extend to rake edge)
24" Certi-label shakes
at 10" exposure
18" felt interlay
2 nails per shake
Solid sheathing
Shake starter course
36" felt
(extend to rake edge)
underlay
Two nails (only) for each
shake approximately 3/4" from
edge and approximately 1 1/2"
above exposure line.
Rafter header
Fascia
Gutter
Adjacent course joints
should be offset
1 1/2" minimum
Rafter
Product should
project 1 1/2"
beyond the fascia
and approximately 1"
over the gable or rake end
Eave protection
(extend to rake edge)
Starter course
Exposure
Space shakes 3/8"
to 5/8" apart
Plywood sheathing
The bottom edge of the felt should be positioned
above the butt of the shake at a distance equal to
twice the weather exposure. Never interlay shingles
with felt.
®
Figure 23a: Certi-Last shake application
(Option 1 depicted)
Note: The above figures are
depicting a shake
application - Do not
interlay shingles with felt.