You should add 2 1 2 to the height of the actual door.
Resizing width for french door.
So if each door measures 30 inches wide the width of the rough opening should be 62 inches.
This will give you room to space the door frame off of the sub floor.
Now all you need to know is how to properly frame your door rough opening.
The standard size of a french door refrigerator is 29 to 36 inches in width 68 to 70 inches in height and 29 to 34 inches in depth.
Sizing up your space.
Measure the width of the studs used to frame the opening.
To get the total width multiply the width of each door by 2 and add 2 inches.
Framing rough opening sizes are really quite simple.
Select from the tools below to find the specific size information you need.
For the height of the rough opening you need to add 2 inches to the height of the door.
Just add 2 to the width of the actual door size.
Whatever width you choose they should be around 2100mm tall around 82 inches.
The most commonly used framing studs have nominal widths of 4 inches 3 5 inches actual and 6 inches 5 5 inches actual.
So if you have a bedroom door that is 30 wide which is considered a 2 6 or 2 6 door just add 2 to the width and frame it 32 wide.
This will help immeasurably as this is the size you ll need to consider.