Pella 80WX0101 - Manual (Page 5)

5
INTERIOR SEAL
CAUTION: Ensure use of low pressure polyurethane window and door insulating foams
and strictly follow the foam manufacturer’s recommendations for application. Use of
high pressure foams or improper application of the foam may cause the window frame
to bow and hinder operation.
A. Insulate between new frame and the existing frame with low
expansion insulating foam. FROM THE EXTERIOR insert the
nozzle of the applicator approximately 1" from the interior stop
and apply a 1" deep bead of foam. This will allow room for the
expansion of the foam and will minimize squeeze out. Follow
foam manufacturer's instructions.
Note: Masking between the window and the existing
interior stop will help alleviate possible squeeze out
of the expandable foam to the interior.
B. Check the window operation by opening and closing
the window. If bowed, remove foam with a serrated
knife, then check operation. If still bowed, adjust shims as
needed, then insulate as instructed in previous step.
C. Inspect the interior and carefully trim all excess foam sealant if needed.
6
EXTERIOR SEAL
A. Insert backer rod into the space around the window
at the head and jambs. This should provide at least
3/8" clearance between the backer rod and the
exterior face of the window.
Note: Backer rod adds shape and depth for the
sealant line.
B. Place a bead of sealant at the jambs and head
between the existing window frame and the
replacement window frame.
Caution: DO NOT seal the bottom exterior
to allow for incidental water to weep.
C. Shape, tool, and clean excess sealant. When
finished, the sealant should be the shape of an
hourglass.
Note: This method creates a more flexible sealant
line capable of expanding and contracting.
EXTERIOR
6A
6B
EXTERIOR
5A
The exposed wood on the exterior stop needs to be covered/
protected. There are many ways to accomplish this, and each case
can be unique.
EXTERIOR FINISH OF EXISTING FRAME
EXTERIOR OF WINDOW
WITH FRAME EXPANDER
A few possibilities include:
a) Covering the existing trim with aluminum coil wrap/
frame expander.
b) Sanding, priming and painting to match existing trim.
c) Covering the exposed wood with a high quality exterior
grade sealant.
Note: The contractor/installer will determine how to
finish the exterior.