Add an extension at the beginning or ending of a continuous railing.
This video demonstrates the following:
For a railing created with a railing type in Revit 2013 or later, you can add an extension to the beginning or end of the top rail or handrail. The extension is defined in the rail type properties.
Press Tab until the top rail is highlighted, and click to select it.
On the Properties palette, click Edit Type to open the Type Properties dialog for the top rail.
In this example, an extension is added to the beginning or bottom end of the rail. For the extension style, you can specify to have the extension attach to the wall, the floor, or the railing post. We'll choose to add a floor extension to the rail.
Specify a value for the extension length (1'), and click Apply to see the changes. Notice that this is a type property, so the extension is added to the ends of both of the top rails.
For an extension at the bottom end of the rail, you can select to add the value of one tread depth to the rail before the extension value is applied.
If you select the Post style for the rail extension, the rail is formed as a loop at the end of the stair and attaches to the railing post.