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.


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

Wednesday, 4 November 2015

RTC Europe 2015 - Revit goes to Budapest

Danube from Pest Castle

RTC Europe is over for another year. The 'Revit Technology Conference' concept is broadening its horizons - it is now all about BIM, not exclusively Revit. This year the event was held in Budapest - the home of Archicad.  Graphisoft were very much in evidence at the event, what with sponsorship and organising tours and competitions.  I think this is a very healthy thing for the industry.  Autodesk and Revit need some effective competition otherwise they will stagnate.

As always, I learned a few more tricks about Revit - in fact quite a few more than normal this time, so this was a very fruitful conference.  We also saw a number of interesting new products on show, such as Enscape, Fuzor and Avail, along with established ones like the Ideate Revit add-ins and CAD Learning - the latter were doing a wonderful job of organising free Revit certification at the conference.

Corinthia Hotel, Budapest

What a spectacular venue for a conference:
Corinthia Hotel Atrium

Stairway to RTC, Corinthia Hotel

Grand ballroom, Corinthia Hotel - main RTC venue

Site Visit to Graphisoft Park

The day before the conference started, a few people went on a tour of Graphisoft Park, outside the centre of Budapest.  We had a guided tour around the technology park set up by the owners of Graphisoft in order to create a good working environment for the Archicad programmers (amongst others).  The park was created on the site of old gasworks, and some of the old buildings were refurbished.

Gasworks Towers at Graphisoft Park
Graphisoft Park, Budapest

Graphisoft Headquarters, Budapest

Original specs on first Mac used for Archicad

Pecha Kucha

This sounds like a Hungarian invention but was actually started in Japan - it is a presentation competition.  Each competitor has 20 Powerpoint slides and 20 seconds to speak on each one.  The inaugural Pecha Kucha event at RTC, sponsored by Graphisoft, was won by Joe Banks of Brisbane, Australia - that means free attendance for him at the next European RTC in Porto, Portugal in October 2016.

Shopping in Budapest

Knockdown sale on Vasari?
Retro mobile phone shop

Monday, 2 November 2015

Revit filter operators - Why Not Or?

Google search logo on 1st November 2015
Google can do it . . . .

So, Why Oh Why (YOY) can't Revit allow 'OR' operators in view and schedule filters?

Revit and and and and and and . . . .
Revit Schedule filter operators

Revit view filters operators

Friday, 23 October 2015

Weird Stair Stuff - part 6 - Showing Concrete Stairs Under Tread Finishes

I was recently asked if it was possible to show a concrete setout plans (and sections) for a monolithic Revit stair that has a tiled finish or timber treads on top of the concrete - ie. to hide the finish and show the concrete riser lines only (which are in a different plan location to the finishes risers shown on the architectural plan).  You would think it should be an easy task given that most structural engineers would want to see only the concrete part of a stair.  Wrong!

By default, in an architectural plan view, Revit displays the finished nosing lines and the hidden riser lines (which may be coincident in plan if you do not have a projecting nosing).  One of the reasons for this is that Revit is not displaying the 3D model in plan views - it displays a hybrid 2.5D version that represents the stair in plan according to Revit's mysterious rules and system controlled subcategories (which are quite frankly, very limiting).
Normal architectural plan view of stair
Changing the Discipline of the view to structural, makes no difference to stairs.  Hiding various stair subcategories will not show the hidden concrete underneath, whatever you try.  If you hover the mouse over the run (and tab to get just a run), it highlights the actual 3D model with all the hidden lines available - but they disappear as soon as you select it - how tantalising!
Pre-select run shows hidden lines of concrete below

If you hide the floor finish at the top of the stair (in this example it is modelled as a separate floor) you can see that there appears to be a gap - this is because Revit stops drawing the plan where it expects the top nosing line to be rather than where the top riser is (even though it does not model the nosing if your stair 'Ends with Riser').
Gap at top of stairs when floor finish is hidden

Back in the section view, if you turn off the 'Treads/Risers' subcategory it leaves just the concrete substructure.

Notice that the concrete actually extends to the back of the riser in section (and 3D) but this is not shown in plan.  The section also has a couple of other issues:
  • The concrete at the top of the stair stops in line with the back of the top riser, where in fact it should extend up until it meets the underside of the floor slab.  Obviously the stair has no knowledge of where that slab is or how thick it is, but there should be a way to deal with this.  There is a Run property for 'Extend Below Slab' so why not have one at the top.
  • There appears to be a joint between the landing and the upper run even though they are the same material - in fact it is a step in the landing because the concrete landing edge aligns with the nosing rather than the concrete riser.  This would need to be manually adjusted if you want them to align or if you want a finish applied to the landing edge.
Concrete Section - treads/Risers hidden
This is getting close to what a structural engineer might want to see, or for an architectural concrete setout drawing.  So how do we get this to display the same information in plan, when Revit really does not want to do so?

As a workaround, we could try using one of Revit's really weird features, as described in my post about stair arrows and detail views:

Detail view callout

Create a detail view callout of the stair.

This type of view (Detail plan view) is actually a true 3D view (a horizontal section), which does not use the normal Revit 2.5D representation of stairs (and ramps).  The stair shows the top riser line (including thickness) and the actual nosing locations where modelled.  In the snapshot below the floor finish is hidden so you can see the top riser.
Stair in Detail plan view type

So now it follows the subcategory rules that normally apply to a section:
  • Nosing Lines, Riser Lines and Outlines are not relevant to this view type
  • Treads/Risers subcategory does apply - try changing the colour override to test it
Treads and risers overridden in detail plan view

Now try turning off the visibility of the Treads/Risers subcategory - and magically you can see the concrete underneath, because that is controlled by the overall 'Stair' category.

Of course there are some downsides to this method of creating concrete setout plans - Detail plan views are not normal Revit views:
  • You cannot place stair path arrows on detail views (although you can place stair numbers)
  • You cannot 'Reference Other View' callouts to regular plan views - so you would have to work out your view referencing carefully.
  • Detail views do not have a 'View Range', so you have to rely on the parent view or 'Far Clipping'
  • View cut plane is controlled by parent view - and cannot be overridden
  • You cannot use Plan Regions
  • If someone deletes your parent plan view, Vamoose detail view.
  • the list goes on . . . . .

Refer to  True 3D RCP View of a Stair in Revit for more uses of this technique
Refer to stair arrows and detail views for more detail on the downsides of this technique
Go to Revit Stair & Railings Index Page

Tuesday, 20 October 2015

Weird Stair Stuff - part 5 - Top Riser Line Missing

Following on from my post about Revit Stair Subcategory Visibility, I noticed another strange anomaly with stairs in plan.
If you have a stair that ends with a riser and has projecting nosings, the very top riser line of your stair will not display in plan.

Run type properties for tread and riser
Run instance properties

Top tread / riser in section

Instead of showing the top riser and nosing lines, Revit will display an 'Outline' line - this represents the actual top nosing line, or where it would be if your run ended in a tread.

End With Tread

If your stair run does actually need to end with a tread, then the subcategory visibility graphics presents you with a different problem:

Run ends with a tread

It displays correctly in section but then you have a top tread that may or may not be the same material as the floor finish - and you get a joint line between the floor and the top tread.  If they are the same material you probably don't want to see the joint line;  if they are different materials you may want to see the joint at detailed views but not in general arrangement views. 
Run ends with a tread
It cannot be controlled by subcategory because you would lose all the outlines (including sides of stair) if you turn off the 'Outlines' subcategory.  So you would need to resort to the 'Linework' tool to hide the line.

The factory has at least corrected the problem of where the stair path arrow ends - on the top riser/nosing line.  With the old stairs it used to include the top tread, which ws totally confusing.

Go to Revit Stair & Railings Index Page

Thursday, 15 October 2015

Weird Stair Stuff - part 4 - Stair Subcategory Overrides

Go to Revit Stair & Railings Index Page

Subcategories (again)

The last couple of posts have been about stair and railing subcategories, which changed in v2013.
I was recently asked two questions about how to override the display of parts of stair.  After my success in finding a workaround with railing overrides, I thought it should be possible to do something similar with stairs, particularly as they are now made of separate components (runs, supports and landings), and have more subcategories . . . .

Visibility Graphics

In the Visibility Graphics dialog box, sadly stair subcategories do not allow individual overrides (except for visibility and lines) - it is the whole stair or nothing [the greyed out boxes in the dialog screen snapshot below are not editable].  Transparency, surface patterns & halftone would all be extremely useful for all or any of the subcategories.

Visibility Graphics Stair Subcategories

View Filters

If at first you do not succeed, try a different tack: 
After encountering a similar limitation on railing subcategories, I tried creating a view filter, which worked for the particular railing subcategory I wanted (although filters are not available for all).
Unfortunately, view filters do not work for any stair subcategory - they just do not show up in the list.  So it is just the stair category - all or nothing again.

Strangely enough there seem to be numerous stair parameters to choose from if you do want to filter the whole stair.  But if you study that list, you'll see that it is only overall stair parameters, and not any of the really useful things, which are properties of a run or landing like "Actual Width", "Monolithic Material", "Tread Material".  So in fact that list of parameters that you can filter by is pretty limiting.

We are running out of options here - its getting desperate:

Override By Element

  • Override By Element works on the whole stair
  • Override By Element does not work on individually selected components such as Support, Run or Landing (it is greyed out when you right-click on an individual stair component).
So that didn't get us anywhere useful.

Linework Tool

What is the second last solution to over-riding things in a view?  The 'Linework Tool'.  Well, that works but it is pretty tedious to work with, and quite clunky - as stairs are system families, you cannot even tab-select multiple lines or the whole component, so it is line by line.

So, first do a temporary transparency override on the whole stair, then use the linework tool to make each riser and tread line dashed:

Then reset the override to remove the transparency - and the tread/riser lines show dashed beyond the support (stringer):
That would have been so much better if we had overrides or filters on subcategories.  Although, having said that, we have the problem that in section/elevation the risers and treads are not distinguished by subcategory - they are all the same (Treads/Riser), which is again very limiting.

Last Resort

What is the last solution to overrides in a view?  Detail lines and masking regions - but we won't even go there because it is absolutely forbidden as far as I am concerned!

In my next post I will talk about the other stair subcategory workaround I had to come up with - and maybe with slightly better results.  But it is a seriously weird workaround.

Go to Revit Stair & Railings Index Page