Wednesday, June 04, 2008

Weird Railings in Revit

Ran across this when working with a team manipulating railings in a Revit project.

Railings typically show the full height of a stair, follow the landing, etc., something like this:

In many cases, you don't want the railing around the landing but only on the bottom & top flights, so you have to remove some of the sketch lines and add an additional railing so you end up with something like this:

You also more than likely don't want to see the entire stair in plan, so you turn off the visibility (or dash) the following sub-categories:

Railings beyond cut line

Stairs beyond cut line
Stringer beyond cut line

Now is when you run into the problem. Since you no longer have one continuous railing that intersects the cut plan, the railing doesn't appear correctly and shows up when it shouldn't (above/beyond the cut plane).

There are probably a few solutions to this, but I'll only list a few...

Solution #1: Hide "element"...

I obviously like to understand what's going on, so I dug a little deeper.

Solution #2: If you look at this in a section and take note of where the upper railing starts, you can correct the display problem by altering your view's top range within the View Range dialog box. Our top range normally defaults to 7'-0", but in this case as long as you have the top range less that where that railing starts, it will not longer show as desired. Here's what I mean -

You can see that this particular railing starts at 5'-6 171/256"...

Adjust the top range below this value. In this case, I adjusted the top range to be 5'-6", just below the railing.

Once I did that, the railing no longer displays! The same thing applies if you want to show the stair beyond the cut plane dashed...

So in review: If you no longer have one continuous railing on your stair, but instead two individual railings (one per flight), the railing on the top will not respect the "do not show beyond cut plane" visibility control because it doesn't interesect the cut plane.

On the same note, you may have the exact opposite situation occur... In our case, we had a very high space with a tall stair. The top railing started well above the top range and the team wondered why it didn't show...

So you can see, we've run into both situations... one where they didn't want the railing to show and one where they did. Once you understand what's going on, you can fix both situations :)