I would wrap right to the OSB and seal that surface between the flange and the OSB with the tape.

I would include some tar paper to weave/tie into the old WRB, but I always prefer to put my tape to the sheathing.

This was done by lowes they used simple red house wrap tape to seal the nailing fins and then went over it with the 4 inch cedar. When I found the 50 foot roll of Pella Smart Smart Flash they did not use I had a bird. I told em they would have to take all the trim boards off to replace the red cellophane like tape. So the 12" siding is cut flush with the removed 4 inches of tar paper. Your saying they should put down a vapor barrier to the edge of the tar paper, wrap around the opening and lay the windows down(so pull out the windows also?)

Then nail the fins down over sheathing and then go over with the Smart tape like they should of? How do you get vapor barrier to abut to to the tar paper or peal the siding back to get under tar paper and tape down?

The jobs been a nightmare from Lowes its a week of downpour rain my windows are waiting to be caulked and I told em the job had to be done right. They asked to use my ladders had no caulk, had to reorder the interior trim boards and jobs now a week old windows are half but put in. Thanks What WRB?

I really mean thanks alot sir! Its gonna stop raining some day and I need to get this done right they said the red tape was fine and OK to just nail fins over OSB dont worry about replacing the tar paper. The cuts are tight thank goodness as we are getting like 3 inches of rain over 5 days not much of an soffett on west side of house.

You might look here for some info. And the window manufacturers instructions should be followed too.

Your not a jerk thanks for explaining I am in healthcare just I would think using Pella instructions is a good place to start. How do you find a good contractor?

These two windows with a colored exterior vinyl Pella 350 not white where 3200 bucks installed not get windows all the time but seemed like I was paying them fairly? One screen was missing, one screen had a hole one had a nick el handle one a white handle just really a bad experience. So I will ask them to take windows out any damage to fins in the process?

Lowes was paid very well, the sub-contractors were not Based on what I know they were Paying about 5 years ago.

Thanks truly for all the help and explanations I had to call Lowes again last night on the urgency I had some seapage around the tops of windows from the 3 inches of rain thru the uncaulked trim I guess. They called me at 5 pm tonight they will be in tomorrow hopefully 3 guys to get it done but we are supposed to get 1-2 inches more tonight. I am lucky some areas to the south got 6 inches

My buddy had a garage installed by a independent, I met today a very small contractor he and other folks use and are happy with so ˆI have someone to go to in the future. He just rolled his eyes and chuckled when I told the story.

The windows should not be relying on a caulk joint to stop water, especially at the head.

Thanks