Measure from outside to outside of casing molding.
How much overlap for barn doors.
A one inch overlap is about ideal so for a 48 finished opening each door would be 24 5 inches wide.
The doors will need to be offset from each other on the track or sometimes even use an extra track.
Again for doorways with moldings measure from the top edge.
I used 7 6 slats which made my doors 42 wide and since my opening is 38 i was able to get 4 of overlap on the doors.
Measure from the header to the floor to determine the door length you need.
Measure across for the width and from the top of the casing molding to the floor for height.
To figure out what size track you need double your final width measurement.
Your door s width should be 2 to 3 inches wider than the door opening and 1 inch higher than the dimensions of your opening.
Add 1 to 2 per door for overlap depending on privacy needs.
Barn door measuring guide for door openings with casing molding.
Barn doors can be installed to overlap each other but it requires a different installation technique and barn door hardware which can increase cost.
Two 24 doors would not overlap at all and would not stay fully engaged into the center guide on the floor.
Doors wider than 24 5 would work just fine but you loose access width when the doors are open.
The picture above is of me seeing how the door will fit on the wall and how it will fit in the opening.