Unusually large door gap
Typically the rough door opening should be about 2 inches wider than the door you are installing (just the door, don't include door frame in this measurement). If you place your pre-hung door and frame into the center of the opening, there should be roughly 1"of total play or 1/2" on each side between the door frame and the rough opening. This 1" of total play will allow you to properly adjust the door for plumb and level. Max gap between rough opening and door frame is 3/4" per side, any larger of a gap and the door installation brackets (available at Home Depot) will not reach far enough to secure to the wall. If your unusual size gap is more than 3.5" larger than your door (not including frame) then you will need to do either 1 of these 2 things:
1. Only use 3 of the 6 door installation brackets. Screw a bracket behind each hinge. Don't install the other 3 brackets. Install the door only using the 3 hinge side brackets based on your drawn level line. This will install the door plumb and level. Then, use shims to finish the other side of the door. Using the brackets on the hinge side will take the hard work out of the installation shimming and plumbing process. All you will need to do is shim the other side based on the reveal (gap between door and door frame). You will be able to shim the unusually large gap.
2. Screw a 1"x4" board to your rough opening that extends from the floor to the top of the rough opening in order to close the gap to a manageable size.
Customer Quote:"Thanks for the help. I only had one door that needed modification. The others were within the 2” margin. It was every bit as easy as your promotional material suggests. Thanks for a great product!" -Rick W.