I downloaded a dyn script from this site:-
It uses ray bouncing to determine the clearance heights.
I am using Dynamo 2.0.3.0.
I then upgraded the rvt to R19 and ran the script.
It gets numerous errors.
For instance, Biomorph node - Faces, throws the following exception:-
The other errors are probably related to the the Biomorp node not operating.
I cannot find a substitute node to replace the Biomorph node however.
If anyone has suggestions - that will be greatly appreciated.
The first images shows an internal issue with dynamo/revit, I think re-installing a stable version would solve it (I had faced it a while back when I wanted to work with geometry related nodes, and only re-installing dynamo fixed it).
Hi habdirad,
Thank you very much!
I installed version 2.0.2.6833 and it now works perrfectly.
Cheers.
Hi @WillGow
Were you running Dynamo 2.0.3 with Revit 2019 or Revit 2019.1? It’s a known issue that Dynamo is quite buggy with Revit 2019. I especially remember toubles with the Python node, but I don’t remember if it also had troubles with the geometry engine.
Dynamo 2.0.3 should be stable 
CC: @jacob.small perhaps?
I’d amend that to say "it has some issues with early ships of Revit 2019. It does quite well with 1.3.4 which I believe is what it ships with, but it’s been like 18 months since I installed it so I’m not sure offhand. 2019.1 is now 13 months old, and 2019.0 is 16 months old.
For now I would make sure that everything is up to date, which at this moment means Dynamo 2.0.3 and Revit 2019.2.2.
FWIW, I am not a big fan of this method. It either fails to catch issues (ie: a pipe running parallel to the edge of the tread, or a wall mounted light fixture that is at the wrong height, a floor that extends over the first 1/3 of a riser), or requires too many points to catch everything you’d need (ie: a 1/8"point grid at each walking surface.
Instead I recommend looking at the geometry of the stair to pull the walkable surfaces (area >= stair width * tread depth && normal at parameter 0.5,0.5 has a Z component of 1) and pull the leading edge of each to build the actual clearance shape, and move that into the rvt file with associated element bindings so that you can update them. Once that mass is added to the file you can use the interference checker in native revit, or any of the many other clash detection tools (navisworks, glue, model coordination, dynamo’s geometry conversion and geometry.does intersect, bimorph nodes, etc.) as you would any other element set.
Hi Jacob,
We were using Revit 2019.2.2.
Thanks for your comments on Ray bounce method. I agree.
In this case, I just wanted a quickndirty solution to use for one project that had a tight deadline and just needed an easy overview solution.
The methodology that you outline sounds very robust. I will try that when I get time.
Thanks again for your response.
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Instead I recommend looking at the geometry of the stair to pull the walkable surfaces (area >= stair width * tread depth && normal at parameter 0.5,0.5 has a Z component of 1) and pull the leading edge of each to build the actual clearance shape, and move that into the rvt file with associated element bindings so that you can update them. Once that mass is added to the file you can use the interference checker in native revit, or any of the many other clash detection tools (navisworks, glue, model coordination, dynamo’s geometry conversion and geometry.does intersect, bimorph nodes, etc.) as you would any other element set.
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Hi Jacob, I’m almost 4 years late on this forum but I’d just shoot. I’m trying to wrap my head around this statement, do you have a sample file and graph on how to do this? - if it’s not too much of a trouble for you of course. Thank you very much!
Ray bouncing is a limited clash detection tool, as it only checks for stuff which falls in the path of the point you project. As a result if you project at the middle of the stair you miss stuff which on the side of the stair, and vice versa. Whereas a solid doesn’t have that issue.
So my preference is to put a solid in place which is built from the leading edge of the nosing first and last nosing in each run projected slight to the landing and lower floor (vector by two points and vector.reverse will get the projection direction). From there you can build a surface by lofting between the curves, copy it up by your required vertical clearance and loft between the two surfaces to get a closed polysurface. This can be pushed into the Revit model as a mass or family instance, which then allows use of standard clash detection tools for as long as your stair remains unchanged.
Best to give it a shot yourself and I’ll try and give some guidance if you get stuck.
