Tyvek/Tarpaper Around Windows

[Matt Fellman]

Does the paper go over or under the side fins on a window or door?

Also, do you install windows and then paper or the other way around. I imagine it can be done either way or I suppose the answer to the first question clears it up.

It's been years since I installed a window and the way the paper is done that I'm taking apart is making me wonder.

[Brandon Whitmore]

You must rely on the manufacturers installation instructions (WRB and window manufacturer).

Typically, the WRB supposed to go on before the window, and then a cut is made, and the WRB is "folded" inside the rough frame. Then sill flashing is installed, the window is installed, followed by jamb and then head area flashing.

Check this out: YouTube - Proper Technique for Flashing and Window Installation (http://www.youtube.com/watch?v=KpqJxbk5qwc)

[Eric Barker]

Ideally the paper is applied over the top and side nailing flanges then taped.

[Markus Keller]

As a contractor, always did it the way Brandon described. Can't agree with Eric's method.

[Jerry Peck]

There are actually two preferred ways:
1) (almost like what Brandon described)
- a) The WRB goes on first, the WRB is cut in and down from each top corner at a 45 degree angle, and in and up from each bottom corner at a 45 degree angle, with both cuts made to leave a flap long enough to go in and wrap over the wall thickness, then a horizontal cut made to connect the two bottom angle cuts together and the two top angle cuts together, then a center vertical cut between the top and bottom horizontal cuts - there are other variations of those cuts which are also good.
- b) The WRB is wrapped up and in, over the sill; wrapped in over the jambs; the top has two slits made at each end at the top creating a flap, which is folded out and up and temporarily taped up.
- c) The back of the window flanges has the proper sealant applied in a proper manner, the window is installed over the WRB and into the opening.
- d) The top WRB is untaped from its temporary position up and laid down over the top flange of the window where it is taped.
- e) The bottom flange is taped across, the side flanges are taped next with the tape extending down and over the bottom tape, then the top is taped with the tape extending out and over the side tape.

2) The WRB is cut as described in 1)a).
- a) The WRB is installed as described in 1)b) except the top is wrapped in and under the header.
- b) The window is installed as described in 1)c).
- c) The top of the window is taped.
- d) The window is taped as described in 1)e.

I prefer method 1) but have seen installation instructions for both 1) and 2).

When using non-fin windows the method more closely resembles 2) as the opening only is taped, with the window being sealed to the sides, top, and bottom of the opening which have been wrapped.

Even with these the WRB may go behind the tape or over the tape and then be taped to the tape.

What it comes down to is: How does THAT window manufacturer say it is to be flashed and done, AND, how does the manufacturer of the tape say it needs to be done, AND, how does the manufacturer of the WRB say it needs to be done. I have seen conflicts between all three, and the window manufacturer takes precedence as THEY had THEIR windows tested as THEY show and state in THEIR installation instructions as it will be THEIR warranty covering their installation.

[Wayne Carlisle]

Try this.