In this example the total width is 38.
How to measure for a sliding barn door with trim.
Add 2 4 to this measurement so your barn door completely covers the entryway without drafts or slight openings.
In instances where casing is present we recommend building the door to the same size as the opening casing.
If your doorway does have a trim measure the width of the door frame from one edge of the trim to the other.
Using a tape measure begin at the left edge of the opening and measure straight across to the right edge.
The opening will have full trim with 3 5 side casing and a 5 5 header see pic for an example of another door trimmed the same way.
Measure from the outside of the casing to the outside of the casing for the door width.
Measure the door opening.
How to measure for a barn door in three steps.
I know that people typically extend the header to encompass the full length of the rail.
Subtracting trim your next step is to calculate the width of the door s opening starting from inside the door jamb on one side all the way to the inside edge of the other.
If your doorway doesn t have a trim measure the width of the inside of the door frame from left to right.
Repeat this step to find the height measuring from the edge of the door header all the way down to the top of your flooring.
If the doorway has moldings measure from outside edge to outside edge to determine the proper door width add about 4 to 6 inches to your measurement.
Not only is it a convenient way to enclose a space it also makes a larger impact on the overall design and aesthetic.