I’m leveling joists in a bathroom floor in preparation for a new subfloor and tile. The bathroom is on the 1st floor with a full height basement below. Two of the joists have a 1/4 inch high spot and I see that they are resting on a door frame header in the basement below where the high spot is. I attached a diagram and a couple of pictures.
Is the right approach to trim the header on the door below which is pushing these joists up or to just plane the high spots on the joists.
If I trim the door header below, do I need to gradually lower the temporary support I would add to do the trimming over time or can I do it in one shot? Also, how much time would it take for the now less supported joists to settle to its final shape/location? Thanks.
-Mark