What is the rough framing dimension for a 30 inch door?

32-1/2 inches.The rough framing should be 2-1/2 inches wider than the door itself. That leaves room for the 3/4 inch finish frame on each side of the door, and then 1/2 inch on each side for the shims between the finish frame and the rough frame.There are some tricks for building frames into new walls that are usually built on the floor and lifted into place.  -- Remember that there are always two studs on each side of the door for strength. -- When building the frame on the floor, install the top and bottom piece of the wall and only the outer studs, the King Stud, for the wall -- now with a door+5

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