From the string of your question, I am assuming you are talking about an adaptive family. You can create an adaptive family perpendicular to a horizontal work plane. In your project, create an array of nodes on a vertical reference plane. Host the family on these nodes and they should horizontal. See screencast.
Remember you also have other options aside from an adaptive family such as line based, face based, or non host family, which you can set them to be always vertical.

