BILT

BILT
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Thursday, 3 September 2015

Weird Revit Stair Stuff - Stair Path Arrows in Detail Plan Views

Here is yet another inconsistency with the (not so) new Revit stair tools.

If you want to create a stair detail drawing, you might start off with a general arrangement plan that has a reference to a stair plan at say 1:20 or 1:50.  Good Revit methodology might suggest creating a callout from your general arrangement plan to generate the stair plan. .  If you do that, the default view type that it wants to create is a "Detail Plan View" - so most people would probably go with that option, without giving it another thought.  Bad move!

Here is where the inconsistency catches you out:  After spending hours setting up the stair sections and annotation on the stair plan, you realise that the stair path arrow is missing.  So you try to place a new one . . . .
Aaaargh!  It is greyed out - so you cannot place a new stair path arrow on your stair detail plan.  However, you can place stair numbers on a component stair in a detail plan view (but not on an old style sketch stair).

Why is this?

2.5D vs 3D 

I believe that it has to do with how a Revit "Detail View" is created:  unlike any other Revit plan view, it is a true 3D section through the model that is cut horizontally.  Other plan views are really only 2.5D because Revit uses all kinds of tricks and shortcuts to represent certain elements in a more traditional plan format rather than a literal slice through the element.  Stairs, railings and ramps are all special element types that have a system controlled 2.5D way of presenting in plan when cut. 
Other categories that might not show true 3D representations would be 'non-cuttable' categories such as furniture ad specialty equipment - they just show a top view.
On the other hand, categories like floors will show a true 3D representation when cut in plan - clearly demonstrated when you use a sloping floor instead of a ramp.
Detail View callout - literal 3D cut plan

Floor Plan callout - 2.5D plan representation

However, all of the above is no excuse for the software developers not to fix the issue so that you can put a stair path arrow in a detail view.

How to solve it?  Well you could just use a line-based detail component (with a built in arrowhead).  But your railings and stair cut lines won't look right either, so you start needing to add break lines, masking regions etc.

There is a better solution:

Plan view vs Detail View

In my opinion, you should just avoid using Detail View types for any plan details.  When placing a plan callout, you should always set the view type to Floor Plan - preferably to a pre-defined type that you have created for specific sorts of details.  Unfortunately Revit keeps reverting back to the Detail View type as its default.  If you forget to set this correctly when creating the callout, you are in trouble as it cannot be changed later.

There are many other reasons for doing this aside from fixing stair plans:
  • Detail views have significant limitations on where and when they can be referenced (see below).  Eg. On a ‘Detail Plan View’ you cannot reference a normal plan view;
  • You cannot change a detail view to a plan view (or vice verse);
  • Plan view callouts allow a different view range to the parent view; detail views have a far clipping offset, which is confusing and does not allow a different cut plane
  • In the Project Browser, Revit groups all Detail Views together (plans and sections), in quite a different place from normal plans - so if you use a mixture of Floor Plans and Detail Views for plan details it becomes a nightmare to organise and find the views.



Reference Other View

In V2016, rules for 'Reference Other View' for callouts are:

In a floor plan view, you can callout 'reference other view' to

  • Any drafting view
  • A detail view callout
  • A floor plan callout (but not a regular plan view)

In a Detail plan view, you can callout 'reference other view' to

  • Any drafting view
  • Any detail view callout
  • Not to any floor plan callout - (this is a big limitation)

In a drafting view, you can callout 'reference other view' to

  • Any drafting view
  • A detail view callout
  • A floor plan callout (but not a regular plan view)


 

5 comments:

  1. Agree... Using the Detail View type of conventional views is a bad idea for anything other than the "end of the road" drafting exercise and one that does not rely on true fidelity of what is shown of the model. For example, symbols embedded Electrical families like outlets and switches do not show up in Detail Views. They need to revisit their design and purpose entirely.

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  2. No elevations able to be created or referenced from detail views either. I only tend to use them for fine scale construction detailing where changes in view range are not required.

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  3. This comment has been removed by a blog administrator.

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  4. Great tip. I forget this every once in a while, Google the issue, and end up right back here. Appreciate the information.

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