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Door flashing technique with #30 felt WRB

evantful | Posted in General Questions on

Im going to begin flashing around the door rough opening to complete my repair work from a rotted rim joist and sill plate from 65 years of water damage.

I just wanted to run this by everyone to get their opinions. Please refer to attached photo as a reference. The siding on the right side will be cut back by another foot.

-The door is a ThermaTru door with a brick mould, the brick moulding will be removed when the door is reinstalled and then installed after all of the weather proofing

Im going to be covering the repair area of the sheathing with #30 Felt.

-In the Door rough opening, before I apply the Felt, on the sheathing under the door sill, apply 9in Vycor Plus across the face, then insert a Jamsill sill pan.

– Then up both sides and wrap the Vycor Plus from the studs out onto the face of the plywood sheathing, shingling into the Jambsill.

-At the top apply more Vycor across the two side faces and wrap into the top of the rough opening.

I will then begin install the #30 Felt WRB across the face of the house, working my way up. When I get to the door with Felt I will cut the felt so it can also wrap into the door rough opening over top of the Vycor and then staple it in the inside edge of the stud just before the dry wall. Working my way open the house shingling the felt as I go.

Does this make sense? Or should I apply the Vycor after the Felt has been installed, with the Felt cut to the outer face of the rough opening (not folding it into the door opening) and then applying and wrapping the Vycor out from the studs over top of the Felt (similar to what you see with new construction house wraps and flashing tape)

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  1. Expert Member
    AKOS TOTH | | #1

    If the felt goes between the door frame and the rough opening all the way to the drywall, you will have a hard time getting good air seal.

    What I did is use wider peel and stick with 1/2 the backing removed. Wrap the rough opening with it and cover about 1" to 2" of the sheathing. Install the WRB, cut it so it ends under the peel and stick. Remove the remaining of the backing on the tape and cover the WRB.

    Remember at the top of the rough opening the correct lapping order. Tape, kick-out flashing then WRB.

  2. evantful | | #2

    Just a follow up question. When applying the Vycor , should I cut back the Felt about an inch or so around the rough opening, exposing the sheathing and then apply the Tape so that it wraps out of the studs and contacts the sheathing and then continues out over the Felt another 3-4inches?

    1. Expert Member
      AKOS TOTH | | #3

      If the plywood is your air barrier, you want the tape to go over it. After sealing up the rough opening to the plywood, then it goes over the WRB.

  3. GBA Editor
    Brian Pontolilo | | #4


    Seems like your work is well under way, but if you still have questions, this video series from FHB shows this process very clearly:

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