How to Guide

PRODUCT GUIDE
Vinyl Single and Double-Hung Windows (JPG006)
8
PROPER WINDOW INSTALLATION
Side jamb
Head jamb
Head jamb
Measure
here
• Proper installation is essential for keeping windows operating
smoothly. If a window fails to operate properly, an inspection is
necessary to determine if it was installed correctly.
• These inspection instructions apply to at window types. Bow
windows, bay windows, and unusual geometric-shaped windows are
more complicated and should be inspected by a window professional.
• A contractor or installer can assist in determining the cause of a
window being “out of specication” and possibly correct it. Window
problems due to improper installation are usually not covered by the
manufacturer’s warranty. For installation instructions, contact us or
your supplier.
• The specications and measurements referenced in this guide are
taken from ASTM E2112 Standard Practice for Installation of Exterior
Windows, Doors and Skylights.
Note: These instructions do not address inspection for proper “water
tightness” or flashing. A “water tight” inspection requires removal of
the exterior siding around the window. Seek professional assistance
regarding this issue.
LEVEL INDICATOR
Accurate measurements are essential in determining level and plumb.
Most carpenters' levels have several bubble level indicators, making it
possible to measure all parts of the window.
Examine the horizontal indicator. If the bubble is centered between the
lines of the indicator, it is level.
If the bubble is not exactly centered, measure how far “out of level” or
“out of plumb” by maneuvering the end of the level until the bubble is
exactly centered. Measure the farthest gap between the level and the
surface. On a 2' level, the gap must not exceed 1/16", or on a 4' level (or
longer), the gap must not exceed 1/8", or the surface is out of
level/plumb.
FRAME TWISTS
Attach two pieces of string to
frame/sash, corner to corner. If
there is a gap between strings at
center point larger than 1/8" for
windows up to 4' wide or high,
or 3/16" for windows larger than
4' wide or high, the frame is not
at. Repeat by switching strings
and re-measuring.
PROPER SHIMMING
Measure width of frame at top,
center, and bottom. If any two
measurements differ more than
1/16", the frame is over or under
shimmed. Repeat process and
measure height of frame.
LEVEL AND PLUMB
For plumb, place level against
each side jamb or use a plumb
bob. For level, place level against
head jamb and sill.
SQUARE
Measure frame/sash from top left
to bottom right corner and from
top right to bottom left corner. If
measurements differ by 1/8" for
windows up to 20 sq. ft. or 1/4"
for windows larger than 20 sq.ft.,
unit is out-of-square.