Revit Railing Path with Fillet Causes End/Top Extension to Fail

[paul.t.macknight]

Hopefully someone can help me. I'm looking to make a crash rail with the railing system in order to better control the length and possible turns around corners than a family would allow (the turn would require a second family be created). However, the end/top floor extension fails immediately following any curve in the railing path that doesn't result in a parallel run with the beginning/bottom line (think Z shaped), and when it doesn't fail it offsets the vertical portion of the floor extension away from the fillet, causing an even worse eyesore than the picture below. I would just allow for the fillet variable in the top rail to create the curve, but the radius of that curve will not necessarily match the radius of the curve going into the floor extension, and the balusters need to be offset from the path's corners more similar to the broken railing.

While I can work around this by not allowing the arc to terminate in a tangent direction with the end line, I may not be the only one using this railing and this drastically reduces its usability for other users. Any help with a solution or insight into what bug in Revit causes this would be greatly appreciated.

Railing path with filletRailing path without fillet

[Viveka_CD]

Hi @paul.t.macknight 

Can you share a file to test further?

Regards,

Viveka

[paul.t.macknight]

I created a blank project with just the railings in it, here you go. Beyond the two railings shown in the pictures are a set of other test rails. They all appear to be working properly either because they follow the Z format or part of the path is slightly offset from the ending line after the fillet command and the offset was trimmed to the arc (creating ≈89° arc instead of the normal 90°), the possible work around I mentioned.

[paul.t.macknight]

A little updated information. I forgot to mention I'm working in Revit 2018, in case it's a version issue.
Also, after a little further testing, the above conditions seem to only be an issue with the top rail when its default join is set to fillet. I tried setting it to miter and it works just fine. While workable, it's still not quite what I'm looking for and would like a solution that allows me to use the fillet option.

[Viveka_CD]

Hi @paul.t.macknight 

Thanks for sharing the file.

I'll proceed with testing it in both versions - Revit 2018 and Revit 2019

Meanwhile, can you confirm that you've installed the latest updates for your Revit version?

• To make sure that the issue you are seeing is not something already fixed in one of the product updates, I would suggest checking the Desktop App to see if there are any Revit updates available. For information on using the Desktop App see the following article: About the Autodesk Desktop App
• Note: If you are not able to download updates through the Desktop App, the following article has information on downloading updates through the Autodesk Accounts page: Install Updates, Add-ons, and Enhancements

Also, can you share a recent playable journal to help me test further?

Thanks,

[paul.t.macknight]

I am a few version behind on 2018 and I unfortunately may not be able to check on the version as a potential issue since we have to go through our IT department for that. I will look into this possibility further to test any possible issues, and compare with my personal copy over the weekend (recent graduate but may not have an updated enough version of Revit to be able to test this issue at home). Otherwise, if the old version ends up being the issue and the bug has since been resolved, I'll just have to wait until we get upgraded at IT's pace.

Attached is the requested journal file, hopefully it'll help.

[Viveka_CD]

Hi @paul.t.macknight 

Thanks for sharing the files.

Even if you are a few version behind, can you specify the update for Revit 2018?  it will help us in comparing and testing the latest version with yours and see if we can reproduce the same.

Regards,

[paul.t.macknight]

Revit version is 18.0.0.420. Pretty out of the box.

[Viveka_CD]

Hi @paul.t.macknight 

Thanks for the information!

I'll do some testing on my end and get back to you.

Regards,

[ToanDN · Accepted solution]

---

@paul.t.macknight wrote:

Revit version is 18.0.0.420. Pretty out of the box.

---

I can replicate the issue.  How about create start/end post families and use them instead of top rail extensions?

[paul.t.macknight]

Thanks for the input! I hadn't thought of a custom start/end baluster. Definitely works, but a little more finicky than I'd like to set up and even more annoying to go in and alter parameters if we have any updates or changes to the crash rails (namely would occur project to project, so I suppose it wouldn't occur too often, but still undesirable). As long as no one else needs to tinker with the thing, we'll be good, but I still would prefer an option that allows the top rail extension to function as intended, much fewer parameters to alter upon changes.

Still, currently best work around for my current situation and provides desired affect. Will mark this as accepted answer for now, but I would still like some feedback from Viveka_CD's testing, hopefully you'll have a way to allow me to use top rail extension.

[ToanDN · Accepted solution]

You can still use the original railing for all other configurations, only switch to the new one (with custom start/end posts) for the Ls or wherever else the defect appears.

[Viveka_CD]

Hi @paul.t.macknight 

As an update from the development team, they are working towards a resolution for this issue.

I will share a public article URL to keep an eye on, please check back with me in a couple of weeks.

Meanwhile the below steps are recommended:

Remove user defined fillets

Add or remove one of the filets

Add a "fake fillet" with extremely small radius just near by existing one fillet

Regards,