Interior seal, Exterior seal – Pella 80WW0101 User Manual

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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. Apply insulating foam sealant. From the interior, insert

the nozzle of the applicator approximately 1" deep into

the space between the window and the rough opening

and apply a 1" deep bead of foam. This will allow room

for expansion of the foam and will minimize squeeze

out. Apply sealant across interior surface of shims

to create a continuous seal. For windows with jamb

extensions installed, ensure the foam is placed between

the window frame and the rough opening, not between

the jamb extension and the rough opening. Follow foam

manufacturer’s instructions.

B. Check the window operation (vent units only) by opening and closing the window.

Note: If the window does not operate correctly, check to make sure it is still plumb, level,

square, and the jambs are not bowed. If adjustments are required, remove the foam with

a serrated knife. Adjust the shims and reapply the insulating foam sealant.

EXTERIOR SEAL

A. Insert backer rod into the space around

the window. 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.

C. Begin the sill sealant bead 1/2" from one jamb, running it across the

sill and stopping 1/2" from the opposite jamb. This 1/2" sealant gap

on each side of the sill allows for incidental water drainage.

D. 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

Interior Finish or Trim: The space between the new window and the existing window’s

frame will need to be covered with trim. There are many ways to accomplish this and each

case can be unique. How this is done will be the decision of the homeowner or window

installer. A few possibilities include using cove, quarter round, or a stop moulding.