Measure ceiling heights

Hi there. I’m trying to make the classic script to calculate ceiling heights with raybound but I cannot make it work for some reason. The point list has no nulls. The 3D view contains only floors and ceilings. Any guesses?

see below link
Measuring ceiling heights (

That’s in fact the script I used as an example to make the one I posted. The one from the link, I run it on my computer and actually I got the same message on the node RayBounce. Maybe is sth wrong on my side, I would have to look it up.

It would be helpful if someone can run my script and tell me if you get the same message. So I can know for sure the issue is on my side. Thanks in advance

00_AA_Test Ceilings.dyn (16.7 KB)

Are the floors/ceilings from a linked model? Out-of-the-box Raybounce does not handle linked models from what I recall, Bimorphs and Data-Shapes packages has content to address Linked Elements.

Hallo Robert, all elements are in the same model.


Looks pretty similar to the script I use to drive parameters, so I’m not sure what’s wrong.

I’ve just run yours and I get some errors, probably because of unplaced rooms, nulls, rooms without ceilings, etc - but it otherwise produces a list of results.

What Revit and Dynamo version are you running? This is working fine on Revit 2020, Dynamo 2.3.

Can you share Revit File & Dynamo File?

Use this nodes, I think here is yours solutions.


If you are dead set on achieving this using the Ray bounce method then by all means continue.

But, if this is just an exercise for wanting to check ceiling heights within the model. Can you not just get the ‘Offset from associated level’ parameter value of each ceiling instance?