I hope its ok to necro this post since I'm still working on this project.
Got the new back door in (sample of the new flooring is sitting in front of threshold).
Had to replace the jack studs, trim the cripples, and put in a proper header above the door. It's nearly perfectly level/plumb. The issue is that the whole house sort of drops down and slopes to the left side of the door. It's probably about 3/4" higher in that corner. Planks will be running parallel with the door but will start on opposite corner. I need to clean up the debris from removing old jack studs & door frame. LOL.
The old sill was not in good shape but it turns out that the rest of the floor beyond it was ok.
Rotted stuff got cut away
New sill is a pressure treated ground contact rated 2x6
There may be room to fit a drip cap of some sort under the new threshold- which pretty much covers the 2x6. Will have to get better pics of that later.
I have a good idea of how to do the flooring up to that point, but I'm still trying to figure out how many inches into the bathroom doorway I should put the vinyl planks. I believe the jamb is 4-9/16" depth. The actual studs are old 2x4s that are 3-3/4" wide instead of 3-1/2" but I don't think that will make too much difference. The transition trim I'm using between new laundry room and bathroom says it needs a 1" gap between materials. The door will swing away from the planks so it will be more flush with the other side.
My questions:
Can I use pre-mixed floor patch to build up some of the difference/slope in front of the exterior door or should I use self-leveling and mix it myself?
If its the latter, is there a good kind that doesn't require wire mesh and only needs primer?
Is there a specific number of inches the planks should go into a 4-9/16" door jamb if the door swings away and I am transitioning to vinyl sheet (needs 1" gap between sheet & planks for reducer trim)?
Any other thoughts?