How to know which size of barn door you need?
The process is simple! You will need a tape measure (preferably a self retracting one!) Read below! Or you can jump right in and build your barn door!
Take note of the Width and Height in feet and inch, for both round to the nearest inch. If there is no door trim and only a case opening just measure the width and height of the case opening itself.
Add 1 inch to both width (W) and height (H) of your measurements and that's the dimensions you need for your barn door!
If the baseboard (add shoe mold if any) is thicker than 1/2 in then you need to add a header (which is a wood plank of the same wood type as your barn door) before installing your barn door! The length of the header should be the same as the rail.
The length of the rail usually is twice the width of your barn door unless otherwise specified.