Old shop door adjustable in height?

Dear people,

I am at the end of my rope. I have to lay vinyl in a retail store, but there are only two millimeters of space under the door and I need 8 millimeters. Can these old doors be adjusted in height? What are the screws on the hinges for?

Many thanks for tips.

Do you currently have 6mm clearance to the frame at the top? If not, adjusting everything won’t help. Plane off 6mm at the bottom (or saw it, depending on the material).

Yes, there are still about 10 mm at the top. So there is sufficient space upwards.

Then try hanging off, placing washers at the desired height on the hinges and hanging back on. Alternatively, shorten it.

The question is, how? This is not a normal front door. Do I have to unscrew the screws or can I just push it up like that?

Just try it, we are no wiser than you because of the three pictures. I suspect that it can't just be pried open, otherwise anyone with a chisel could enter the store (?). So first, loosen the hinges. A flathead screwdriver would be my first tool to try.