Message: Roof and ceiling planes cannot be found or they are too close together, so cannot make truss.

The information in this article applies to:

QUESTION

When I draw a truss, I receive the following message:

"Roof and ceiling planes cannot be found or they are too close together, so cannot make truss."

Why does this happen?

ANSWER

A roof truss can only exist in a space defined by the roof planes above it and the ceiling below it. This is because the shape of a truss is defined by the location of the roof and the ceiling.

If the program either does not find both roof and ceiling planes, or if there is not enough room between them to model a truss, this warning message will display. One common example is if a truss is drawn in a roof overhang where there is no ceiling.

The incorrect truss may still display in plan view with a label of the form “TR-*”. If it does, it should be deleted or moved.