"Can't make type..." error when placing joists

Hey everyone! I'm excited about contributing to the Revit Clinic - and happy to be able to get some more Revit Structure content out there!

I'm originally from a suburb on the north shore of Boston, MA. I attended the University of New Hampshire, where I received a degree in Civil Engineering (focusing in Structural Engineering). After college I relocated to California where I worked as Project Coordinator/CAD Designer for an architecture firm. I started at Autodesk in 2005 working mainly with the architectural products, but soon grew into the team expert for Revit Structure. I now live in beautiful Charleston, SC and love every day of my job. Life is good. :) Since I just recapped and spoiled most of my "About the Authors" section, I'll leave you in suspense about what I enjoy outside of work - you can read my bio.

For my first post, I'd like to address a common error you may receive when placing a joist or a beam system of joist members:

“Can't make type ‘LH-Series Bar Joist: 24LH05’” (substitute the particular joist you're adding).

This is due to both family and manufacturer limits. Using the 24LH05 as an example, the shortest valid length is 20'-0". If you try to place one shorter than that, you'll receive the error. This is because in order for the family to be valid, it needs a set of internal panels, and a variable and end panel on each end.

Though the types of panels may differ, this concept applies to all web joist families built with panel arrays/groups: K-Series, LH-Series, SLH-Series, DLH-Series Bar Joists; and Joist Girders.

I hope this clears that error message up! Please feel free to leave feedback if there's anything in particular that you'd like me to post about for Revit Structure, and I'll be happy to try to cover it!

Comments

[Justin]

Great topic!!! There is nothing more frustrating than getting this error. The problem being that we (structural engineers) would still spec a joist for this area. It may be 200mm deep but we would still spec it and the manufacturer would still provide us with it. I have looked into the family and have noticed that if you do play around with some of the variables dealing with the aray, you can get it to work. There should be a better way to do this. I shouldn't admit this but we have found in the past that we needed to fake framing in different situations.

JB