Installation Instructions
Verify Square, Level, and Plumb
A
B
D
C
E
A
B
D
C
E
Sealant 
joints
Liquid 
applied 
ashing
INSTALLATION INSTRUCTIONS
for Vinyl Windows with Integral Nailing Fin (JII001)
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REMOVE PACKAGING AND INSPECT WINDOW
INSPECT ROUGH OPENING
REMOVE PACKAGING
Remove shipping materials such as corner covers, shipping blocks or 
pads. If there is a protective lm on the glass, do not remove it until 
installation and construction are complete.
INSPECT WINDOW
• Cosmetic damage
• Product squareness (diagonal measurements not more than 1/4" 
different)
• Correct product (size, color, grid pattern, handing, glazing, energy-
efciency requirements, etc.)
• Verify the width and height 
of the window are each 
1/2"-5/8" smaller than the 
rough opening width and 
height. Mulled units should be 
3/4" narrower.
• Verify the rough opening 
is square. The (A) and (B) 
measurements above should 
be the same. Maximum 
allowable deviation from 
square is 1/8" for windows 
20 sq. ft. and smaller, and 1/4" 
for windows larger than 
20 sq. ft.
• Cracked frame welds or other frame damage
• Splits, cracks, holes, missing sections or other damage to the nailing 
n longer than 6" and/or within 1/2" of window frame
• For side-by-side mulled units, a drip cap that extends the length of the 
frame plus 1/8" overhang on each end is required.
If any of the above conditions represent a concern, or if you expect 
environmental conditions to exceed the window's performance rating, 
do not install the window. Contact your dealer or distributor for 
recommendations.
• Verify the rough opening is level and plumb (C) and (D). The 
maximum allowable deviation is 1/16" for every 2' of rough opening 
(not to exceed 1/8").
• The rough opening sill must not be crowned or sagged (D), but rather 
level or sloped (positive slope) to the exterior. 
• The exterior face of the rough opening must be in a single plane (E) 
with less than 1/8" twist from corner to corner.
• Minimum double studs (king and jack/trimmer) should be used to 
support the header at all rough openings.
FOR RETROFIT INSTALLATIONS
After removing the old window, remove sufcient cladding (siding, 
stucco etc.) to expose enough intact building wrap to properly seal 
the window to the opening. If damaged, apply new building wrap in 
shiplap manner. Verify the rough opening framing is structurally sound. 
Contact your local waste management entities for proper disposal or 
recycling of products being removed.
PREPARE BUCK
Note! This section applies to 
installations into a masonry 
wall only. For installations into 
a stud-framed wall, begin with 
section 4, “PREPARE STUD-
FRAMED WALL.”
1. Seal any joint larger than 
1/16" in the buck and 
between the buck and the 
concrete/masonry with 
sealant.
2. Cover the buck and the 
surrounding concrete/
masonry at the head and jambs with liquid applied ashing as shown.
3. If installing into a four-sided buck, seal the sill in a similar manner.
Note! Where the window will sit on the sill, shim to provide continuous 
support to the sill. This shimming must be 1/2" shorter than the width 
of the window frame, be 1/4" narrower than the depth of the window 
frame sill, should level the rough opening sill and be no more than 
1/4"thick.
4. Align the shimming on the sill ush with the exterior and centered 
between the side jambs. If installing a mulled unit, leave gaps at the 
mull joint(s) so they don't sit on the shimming and tack into place or 
secure with sealant. SKIP to section 5, “INSTALL WINDOW.”
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