Installation Guide

ENGINEERED WOOD CONSTRUCTION GUIDE
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FORM NO. E30V
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© 2011 APA – THE ENGINEERED WOOD ASSOCIATION
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WWW.APAWOOD.ORG
67
Roof Construction
Only Exterior panels should be used for closed soffits.
At eaves where Exposure 1 sheathing is used for roof decking, protect panel edges against direct exposure to the weather
with fascia trim.
Although unsanded and touch-sanded grades of plywood are often used for applications such as soffits, optimum appear-
ance and finish performance is attained by using panels with textured or sanded A-grade faces. For panel grades other
than APA RATED SIDING 303, top-quality acrylic latex house paint systems provide best performance (see page 55).
Face-checking (separations between fibers parallel to the grain of the face veneer) can be expected on non-overlaid ply-
wood which is exposed to the out doors, even when finished. If a smooth, check-free surface is desired, use Medium
Density Overlay (MDO) plywood.
TABLE 37
APA PANELS FOR CLOSED SOFFIT OR FOR NONSTRUCTURAL CEILING
(a)(b)
(Strength axis across supports)
Maximum Span (in.)
All Edges Supported
Panel Performance
Category Species Group
Nail Size
and Type
(c)
24 11/32 APA
(d)
All
Species
Groups
6d nonstaining
box or casing
32 15/32 APA
(d)
8d nonstaining
box or casing
48 19/32 APA
(d)
(a) Space nails maximum 6 inches at panel edges and 12 inches at
intermediate supports for spans less than 48 inches; 6 inches at
all supports for 48-inch spans.
(b) For appearance purposes, blocking, tongue-and-groove edges
or other suitable edge supports should be provided.
(c) See Table 5, page 14, for nail dimensions.
(d) Any suitable grade panel which meets appearance require-
ments – Exterior for closed soffits, Exposure 1 or Exterior for
nonstructural ceiling.
TABLE 36
APA PANELS FOR OPEN SOFFIT OR FOR COMBINED ROOF DECKING-CEILING
(a)(b)
(Strength axis across supports. For APA RATED SHEATHING, where appearance is not a major concern, see Table 30.)
Maximum Span
(inches)
Panel Description
(All panels Exterior or Exposure 1)
Species Group
for Plywood
16
Performance Category 15/32 APA RATED SIDING 303 1, 2, 3, 4
Performance Category 15/32 APA MDO, Sanded and Touch-Sanded Plywood 1, 2, 3, 4
24
Performance Category 15/32 APA RATED SIDING 303 1
Performance Category 15/32 APA MDO, Sanded and Touch-Sanded Plywood 1, 2, 3
Performance Category 19/32 APA RATED SIDING 303 1, 2, 3, 4
Performance Category 19/32 APA MDO, Sanded and Touch-Sanded Plywood 1, 2, 3, 4
APA RATED STURD-I-FLOOR 16 oc —
32
Performance Category 19/32 APA RATED SIDING 303 1
Performance Category 19/32 APA MDO, Sanded and Touch-Sanded Plywood 1
Performance Category 23/32 APA Textured Plywood
(c)
1, 2, 3, 4
Performance Category 23/32 APA MDO, Sanded and Touch-Sanded Plywood 1, 2, 3, 4
APA RATED STURD-I-FLOOR 20 oc —
48
Performance Category 1-1/8 APA Textured Plywood
(c)
1, 2, 3, 4
APA RATED STURD-I-FLOOR 48 oc —
(a) All panels will support at least 30 psf live load plus 10 psf dead
load at maximum span.
(b) For appearance purposes, blocking, tongue-and-groove edges or
other suitable edge supports should be provided.
(c) Also see Table 30 for APA RATED SHEATHING/CEILING DECK.