Installation Guide

W valley metal 1/2" crimp
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2
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Figures 13a-13d: Flashing Details
for Shake and Shingle Valleys
Figure 13c: Valley Product Application
Figure 13d:
Roof Valley Flashing Detail
ROOF VALLEY FLASHING DETAILS
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Figure 13b: Typical Saddle Flashing Detail
36" valley felt (left side)
36" valley felt (right side)
1/2" folded
back trim
W valley metal
W valley metal lapped
at ridge (2" lap)
Order of applying Certi-label
shakes or shingles at valley:
1. Stop course line here
2. Place pre-cut valley piece so
that cut-angle is positioned
on the valley guide chalk line
with tip on the course line.
3. Select product of the
required width to complete
the course of Certi-label
shakes or shingles.
Keep nails well away from
the center of valley
Hidden felt
Courtesy: Western Wood Products, Photo: John Spaulding
Valleys: Certi-label Shingles
Valleys: Certi-label Shakes
For roofs with slopes of 12:12 or greater, valley
flashing should extend not less than 8" on
each side of the valley centerline. For roof
slopes less than 12:12, flashing should extend
not less than 11” each side.
. Shingles should not be applied with their
grain parallel to the valley centerline and those
extending into the valley should be cut at the
correct angle (Figure 13b).
Metal
valleys should be center-crimped, painted,
galvanized steel or aluminum and should
extend not less than 11" on each side of the
valley centerline. In some areas, however,
flashing width requirements may differ and
local building codes should be consulted.
Shakes should not be applied with their grain
parallel to the valley centerline and those
extending into the valley should be cut at the
correct angle (Figure 13c).
Valley metal
should be underlayed with No. 30 ASTM D226
Type II or No. 30 ASTM D4869 Type IV roofing
felt
On shake roofs, it is recommended that a strip
of No. 30 ASTM D226 Type II or No. 30 ASTM
D4869 Type lV roofing felt be installed over the
sheathing and under the metal valley.