Pella 812W0100, Installation Instructions Manual

3D

3C

3D

C. 

Fold down top flap

 of water resistive barrier (3C).

D. 

Apply flashing tape to diagonal cuts

. Cut pieces of 

flashing tape at least 1" longer than the diagonal cuts in 

the water resistive barrier. Apply the tape covering the 

entire diagonal cut in the water resistive barrier at both 

upper corners of the window.

Note: Be sure to overlap the top corners (3D).

2

SETTING AND FASTENING THE WINDOW (continued)

M. 

Drill 1/8” x 1” deep pilot holes

into the rough framing through the 

clearance holes in the unit frame.

N. 

Install #10 x 3-1/2” corrosion 

resistant wood screws

 into each of 

the clearance holes. 

Note: Drive the screws snug but DO 

NOT over-tighten the screws. DO 

NOT bend or bow the unit frame.

#10 x 3-1/2"  

corrosion resistant 

wood screw 

Drill 1/8" diameter pilot  

hole through the clearance 

hole in the frame 

2N

2M

Note: The flashing tape must be applied 

approximately 1/2" onto the frame cladding at the 

jambs and head. Pre-folding the tape at 1/2" before 

removing the paper backing will make it easier to 

apply the tape correctly. If the siding is less than 1/2" 

thick, adjust the dimension of the fold so the exterior 

sealant line will cover the exterior edge of the tape.

3

INTEGRATING THE WINDOW TO THE  

WATER RESISTIVE BARRIER

Flashing 

Tape

Rectangular Units Only:

A. 

Apply side flashing tape

. Cut two pieces of flashing 

tape 4" longer than the frame height of the window. 

Apply one piece to each side 1/2" onto the frame 

cladding, over the nailing fin and onto the water 

resistive barrier. The tape should extend 2" above the 

top of the window and 2" below the bottom of the 

window. Press the tape down firmly while folding 

down the excess tape at the top and bottom of the 

window.

B. 

Apply top flashing tape

. Cut a piece of flashing 

tape long enough to go across the top of the window 

and extend at least 1" past the side flashing tape 

on both sides. Apply the tape 1/2" onto the frame 

cladding, over the top nailing fin as shown. Fold 

the overlapping tape down, and press all tape down 

firmly.

Note: DO NOT tape or seal the bottom nailing fin.

3B

3B

1"