For doors between 90 inches and 120 inches use four hinges.
3 hinge position on doors.
For doors up to 2 1 4 thick the hinge is set back 1 4 from the back face of the door.
Hold the door in place using blocks under the bottom to support it if necessary.
Use three hinges if the door is between 60 and 90 inches tall.
Line up the two hinge plates so that the ones on the door match the ones in the jamb.
Because gravity works on a door in this way hinges are placed on the high side with the bottom hinge 10 inches from the bottom of the door and the top one 5 inches from the top of the door.
This keeps the top of the door from rubbing on the frame opposite the hinge.
Once all the hinge positions are marked remove the door from the lining place it in the saddle and wedge it hinge side up.
The top hinge is a little closer to the top usually about 7 as it is always in tension with the forces applied.
Connect the door to the jamb.
Wood metal door and hollow metal frame door is inset approximately 1 8.
In general you ll want to use one hinge for every 30 inches of door height.
Use two hinges for doors up to 60 inches tall.
Bigger solid core doors require 3 or 4 or more hinges with ball bearings.
Once these dimensions are known the formula can then be applied.
Hinges are generally spaced out equally to also keep the door straight.
For doors over to 2 1 4 thick the hinge is set back 3 8 from the back face of the door.
Slide the hinge pins into place and remove the blocks from the door.
Center hinge is equally spaced between top and bottom.