If you want it to completely cover your overhead door trim you ll have to measure from the top of that down instead of just inside the door.
Interior barn door opening overlap detail.
First make sure that the header space over the opening can support the weight of the hanging barn door.
To have privacy the door usually overlaps the opening by an inch so that a 2 6 opening will require a 2 8 door.
You will cut your slats exactly the height of your opening minus whatever clearance you want the door to have above the floor i wanted mine to have 1 2 inch between the floor and the door.
Measure across for the width and from the top of the casing molding to the floor for height.
The final option is bypass doors.
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.
Measure from outside to outside of casing molding.
This application is great for areas where barn doors are desired but there isn t adequate room on either side of the opening for the door to slide.
In this application the doors overlap and slide over one another so that half of the opening is accessible at any time.
The determining factor in how high or how wide you want to go is just how much you want your sliding door to overlap with the opening.
Add 1 to 2 per door for overlap depending on privacy needs.