Sure you can, as long as its 1 3/4" bigger uniformly top to bottom. 2 "s is ideally better since with the extra width you can tilt the door to allow for out of plumb openings, but as long the opening is plumb, or if not, you don't care that it's not perfectly plumb, then go for it! You're just going to have a little less room to play with.
When adding to an existing building where metal studs are being used it is best to cut-out close to a corner or vertical support. From those points a floor support joint as well as additional support can be constructed as needed.
The rough opening of an interior door is two inches wider than the width of the door and two inches higher than its height. Thus your rough opening width is 38". A typical interior door has a height of 80" which would require a rough opening height of 82" but check your door to ensure that is theheight.
Make your rough opening 2 1/2 inches larger on the width and height.
Rough opening are 2" wider and 2-2 1/2" taller than than the door itself. 2/8" door needs a 2/10" wide opening.
The rough opening width for a 24" door is 26-1/2" The rough opening height for a 24" door is 26-5/8" Rough openings are 2" wider and 2-1/2" taller than the actual door. This allows room for the door frame and adjustment.
Rough opening is an opening in a wall, or the framework of a building, into which a door frame or window frame, subframe, or rough buck is fitted.It is a measurement that a manufacture needs for installment of their component applications.
sill opening of a wall
In most cases rough opening is 38 1/4x82 1/2.
1/2inc all around
For a 30" door, the rough opening would be 32" in width and 82" in height. Check with your local building inspection department just in case a larger door is required.
Add 2 1/2" to both dementions. for a 36" x 6'8" door you would frame 38 1/2 x 82 1/2".
You are supposed to measure the "rough" opening. This is distance from the studs that line the door opening. (not from the door frame itself) Top to bottom then from side to side. If you already have a door there and are just replacing it then you can just measure the door and get one of the same size. Good luck.