Learn window and flashing installation. Learn how to keep the water out💪 #window #flashing #learn, by BAS Renovations on YouTube. 2 min 59 s.
- Video length
- 2 min 59 s
- Time to do it
- 1 hour per window
- Difficulty
- Medium
- Steps
- 8
What you need
Steps
Measure the width and height of the rough opening. Cut self-adhesive flashing tape about 4 inches longer than each side so the pieces overlap at the corners.
Brush off dust and let the sheathing dry. Wipe on primer if the tape maker asks for it, so the tape sticks and stays stuck.
Press a sill pan or sill flashing tape into the bottom of the opening first. Tilt it slightly toward the outside so water runs off, not in.
Run jamb flashing up each side, starting at the sill and working upward. Overlap each piece by at least 2 inches, shingle style.
Fit the head flashing last, over the top of the side pieces. Tape the ends so water running down the wall passes over the window, not behind it.
Set the window into the opening, shim the corners until it is level and plumb, then fasten through the flanges the way the maker specifies.
Fill the gap between the frame and the rough opening with backer rod and a bead of exterior sealant. Leave the weep holes at the bottom open so water can drain.
Check every joint by eye and run a finger along the tape edges. Re-press any lifted corner with a roller before the wall gets closed up.
Tips and common mistakes
Never tape over the weep holes at the bottom of the frame, because trapped water rots the sill.
Always lap tape shingle fashion, with the upper piece sitting over the one below it.
Cold weather weakens the adhesive, so warm the tape in your hands before you press it down.
Stand on a stable ladder and cut tape with the blade moving away from your body.
Questions
Do I still need flashing tape if the window has a nailing flange?
Yes. The flange holds the window in place but does not seal it. Tape laps over the flange and carries water out to the siding.
Can I just fill the gap around the frame with expanding foam?
Use low-expansion foam only, and keep it away from the bottom of the opening. Standard foam swells hard enough to bow the frame and blocks drainage.
How much should flashing pieces overlap?
At least 2 inches along the side laps and about 4 inches where pieces meet at the corners.
This guide was drafted from the video's details and general task knowledge. It has not been checked against the full video. Check the video and relevant product instructions before following a procedure. Report a correction.
