what is rough opening width
For a 6' 8 high door (80 inches) I like to frame my rough opening heighth at 82 3/4. This allows room for all the situations mentioned above. If your header material is a. double 2x12, holding it to the top plate will give you that heighth. Rough openings for door widths are pretty much standard. The rough opening width is 2 inches wider than the door itself. this allows room for the door jambs which are usually 3/4 thick. This gives you approximately 1/2 of play and shim room when installing a prehung door. For a 36 door (3' 0) the rough openig width would be 38.