Most barn door sizes fall anywhere between 36 wide on the shorter side by 96 tall on the longer side.
Interior barn door opening overlap detail.
Measure across for the width and from the top of the casing molding to the floor for height.
Double barn doors require open wall space on both sides of the doorway.
Add 4 to the measurement and you have your recommended door width.
Measure from outside to outside of casing molding.
Keep in mind that light switches electrical outlets and heating and cooling registers on the walls next to the opening could be in the way.
For example a 4 foot door will cover a 3 foot opening with 6 inches on either side reducing the gaps.
Measure from inside to inside of the opening.
For complete coverage and to minimize the gaps make sure the door is at least several inches wider than the opening.
To have privacy the door usually overlaps the opening by an inch so that a 2 6 opening will require a 2 8 door.
Total door width will be 36.
This means on one side of the door opening or the other there should be at least 2 8 and perhaps a little more to ensure all the hardware can fit properly.
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.
Barn door measuring guide.
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.
Again for doorways with moldings measure from the top edge.
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.
Ideally the door will cover 2 to 3 inches beyond the opening on each side.
Barn doors hang from a track outside the room covering the doorway but leaving gaps at the sides between wall and door.
For door openings with casing molding.
The final option is bypass doors.
Sliding barn doors work best when there is enough empty wall space next to the opening that the door can slide completely open.
Measure from the header to the floor to determine the door length you need.
To figure out what size track you need double your final width measurement.
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.
In this application the doors overlap and slide over one another so that half of the opening is accessible at any time.
Add 1 to 2 per door for overlap depending on privacy needs.
Sheetrocked opening no trim or casing width.
In this example the opening width is 32 4.