Installation Guide

Figure 1: Spaced Sheathing
For applications using varied exposures, the center of the
sheathing board should be equal to the distance of the exposure.
Figure 3: Spaced Over Solid Combination Sheathing
This is the preferred system for shingle application, in areas with high humidity or where additional
ventilation is required. When using Certi-Last products, they may be applied directly to the deck.
Rafter
Rafter header
Fascia
Product should project 1 1/2
beyond the fascia and
approximately 1"
over the gable
or rake end
"
approximately 1"
over the gable
or rake end
Product should project 1 1/2
beyond the fascia and
"
Spaced sheathing
Eave protection
(extend to rake edge)
Certi-label shakes
Solid sheathing
Figure 2: Solid Sheathing
Rafter
Rafter header
Fascia
Eave protection
(extend to rake edge)
GENERAL DESIGN AND APPLICATION DETAILS
3
Certi-label shakes
Note: in areas of high humidity,
nailing strips or a continuous
ventilation product may be
used, or Certi-Last treated
shakes may be applied directly
to the deck.
Product should project 1 1/2
beyond the fascia and
approximately 1"
over the gable
or rake end
Gutter
Certi-label shingles
Eave protection
(extend to rake edge)
Solid sheathing
Rafter header
Fascia
Rafter
2 x 4 spacers
1 x 4 or 1 x 6
nailing strips
Solid sheathing at eave
Solid sheathing at eave
Gutter
Gutter
Sheathing
Staggered Butt Applications
Shakes and shingles may be applied over
spaced sheathing. Spaced sheathing is usually
1 x 4 or 1 x 6 softwood boards and shall not
be less than 1 x 4 boards.
Solid sheathing is recommended for shakes
and may be required in seismic regions or
under treated shakes and shingles. Solid
sheathing is used in areas with wind-driven
snow. Please note that the only solid sheet
sheathing tested with Certi-label shakes and
shingles is plywood. Check with your local
building official for plywood
thickness/dimensions. Eave protection is used
on the edge where 36" felt underlay is used
and should extend up at least 24" beyond the
exterior wall but it is not meant to cover the
entire roof.
Staggered butt applications are made by
shortening the exposure less than the greater
maximum exposure. No shakes or shingles
shall be applied greater than the maximum
exposure allowed. Check with local building
codes for approval of this installation method.
Note: Do not cover the entire deck with
. See CSSB
technical bulletin “Asphalt-Saturated
Organic Felt”.
non-permeable underlayment