Wednesday, 11 November 2015

True 3D RCP View of a Stair in Revit

I was asked recently if there could be a way to show a true reflected ceiling plan (RCP) of a stair in Revit.  If you set up a conventional RCP view in Revit, it will display the underside of a stair above as if it has a smooth sloping soffit regardless of the construction.  A steel of timber stair will look just like a monolithic stair above - it shows the outline of each run and landing plus any supports, but no back of riser lines.  It makes no difference changing the view discipline to 'Structural'.





You can check which subcategories it is displaying by changing the view overrides:
<Above> Outlines   and   <Above>Supports


For more info, refer to Stair Subcategory Visibility

For a metal or timber stair, you would expect to see the undersides of the risers;  a precast stair might be the same.

Workaround

There is a way to achieve this, but of course it is a workaround that has several downsides.  What you need to do is create a plan callout of the stair, but it must be made as a detail view.  For more information on the downsides, refer to Detail Plan Callout Views.

When you create a callout from a floor plan view, you have a choice of making it a detail or a floor plan view. 


These behave very differently and are not interchangeable, so you need to choose the right one from the start.  Normally I would strongly advise to never use a Detail Plan View callout, but this is one exception to that advice - so go ahead and create a Detail Plan view.
 When you go to the callout view, it shows a true 3D representation of the stair, without any cutlines or representations of what is above.  It also cannot host a stair path arrow (amongst other things).
Detail View plan callout of a stair
This callout view can be converted to a reflected ceiling plan view by following a few steps:
  • Select the callout and change its properties:
  • Show In = Intersecting Views
 
  • Parent View = <none>

 
  • Far Clipping = Clip without Line
  • Far Clip Offset = a suitable view range distance to see the whole stair
  • Go to a section view that cuts through the plan callout
  • You should see the callout as a horizontal section line (if not, check its extents to see it is withing the section extents) - select it
  • Click on the 'Flip Section' double arrow symbol - it should now be looking upwards
  • Go to the callout view, and it should be a reflected ceiling plan
RCP Detail callout view
The subcategory display of this will be quite different from a normal RCP view - refer to Showing Concrete Stairs under tread finishes
The riser lines will be controlled by the 'Treads/Risers' subcategory.  The Nosing Lines and Riser Lines subcategories will not affect this kind of view.

I would only recommend using this workaround for detailed RCP views of stairs.  I would not use it on an overall RCP of the whole floor - I would accept the fact that undersides of risers will not display on the overall.

 Stairs index page

5 comments:

  1. Amazing workaround, Tim, thanks for sharing. When I read your message in Revitforum, I said, "how can you reverse the view of a callout detail view. Now I see. Hehe...:) thanks!

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  2. Unfortunately this also mirrors the ceiling plan view. If you try creating a stair at angle, you will see what I mean. Not sure if there is a way to fix it.

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  3. Hi Stealthnye,
    I don't believe that it does mirror the RCP - it should create it in exactly the same orientation as a traditional RCP. I have tested it multiple times. What do you mean by creating a stair at an angle? Non-orthogonal or with a crank in it?

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  4. this doesn't work, the view will end up mirrored you can not overlap it on a reflected ceiling...

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  5. OK, I get what you mean - it is mirrored about the X axis. I was assuming the original comment meant around the Y axis. We'll need to give it some thought to come up with a solution.

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