[masraum]

If you were building a rough opening for an old (100y) home that's not got a level, straight surface in it, how would you tackle the issue that I'm about to describe.

Let's say that you measured up from the bottom plate to the height of the top of the trimmers to plan where to put the header. And you cut the header to fit, and when you put the header in lined up with the 2 lines on either stud, you discovered that the header was not level. Now the header is going to essentially just be something to attach the top of the door frame to, so it's probably not hugely vital. But you can leave the header crooked or you can make the header level.

Would you make the header level (studs are plumb, so trimmers will be as well)?



If the studs/trimmers are plumb, and the header is level, then those 3 things will be square to each other. What that means if the measurement is off is that the floor is going to be off which means that the gap between the floor and the bottom of the door is going to be off.

So, what would you do?

I think that having the sides and top level, plumb and square will make the rest of the door frame build/install much easier and better.