Revit Stair Wall Joins in Section

Following on from an earlier post about joining stairs and floors, I just wanted to clarify what happens when you try to join Stairs and Walls in section . . . .

We saw previously that Revit does have some limited capability to join stairs and floors at the base of a stair - but it has many limitations.

Joining a Wall and a Floor

All good Revit users would know that if a floor and a wall are of the same material, and they have coincident or overlapping edges, they can be "joined" in the model.  This is not just a graphic tool that is done per view - it affects the model in potentially all views, including material quantity schedules.  If an overlapping wall and floor are joined, the volume of material that was previously counted twice is corrected after the join so it is counted once.

Join Geometry

Select floor and wall to join

Floor and wall are joined

Providing that the elements are of the same material, the line between the floor and wall disappears.  In this example, the 'Level' line is revealed, as it happens to align with the top of the floor.

Joining a Wall and a Stair Landing

 

Try the same thing with a wall and a stair landing . . .

What happens?  Absolutely nothing.  After selecting the wall, Revit will not even highlight the stair landing (or vice versa if you select the landing first).

Well, that is just plain ridiculous!  You might argue that the wall and landing would be cast separately on site, so there should always be a joint line between them - but the graphic convention is to not show a line, or at least show a thinner line between them in section.

 

What to Do?

There is no good workaround to this problem - each method is clunky and not robust.

Linework Tool

Linework Tool

If you try the linework took, you immediately discover that it will not do the job for you, as it affects the whole wall.

That isn't very helpful, as you only want a small segment of the wall edge line to be invisible (or thin line).

Another strange Revit quirk with the linework tool is that when you select a line in elevation (or projection in plan) it gives you blue dots at each end , which can be dragged so that only part of the line has its style overridden.  That is a very useful capability - but infuriatingly, it does not work on cut lines.

Yet another quirk is that the underside of a run is treated as one line when cut (section), but in elevation, each step is a separate line segment.  Why, or why?

Filled Region

Filled Region

A common method of hiding a multitude-of-sins in Revit is to use Filled Regions.  These have pros and cons:

• They are quick and easy to understand for most users

• Their edge lines can be of different styles, including "invisible" as part of the sketch - so they hide model lines underneath 

• They will merge with underlying element hatching , providing the material hatch style matches the filled region hatching

• They are view-based, so any patching up on one view will not show on other views

• Line edges/junctions can be messy when viewd close-up

• If the model is changed, the filled region will not change with it (unless you constrain the sketch lines, which is not generally advisable - as your model very quickly becomes over-constrained and unworkable)
  

Cut Profile

Cut Profile (View Menu)

You could try the 'Cut Profile' command - this allows you to modify how an element looks in a particular view.  Once initiated, it takes you into sketch mode - so you can draw a shape to add to an element (or cut from it).

The end result is not very promising in this situation

• The added shape does not obscure the wall line in the way that a filled region does
• The sketch lines cannot have a line style (unlike Filled Regions)
  

The worst thing about this idea is that the Linework tool does not work at all on cut-profile shapes - thus making this tool almost useless!

Conclusion

Sadly there is no clever workaround.  The conclusion is that it is not worth fighting Revit on this one - just accept the joint line between wall and landing.  In many cases it is not an issue, but when the stair and wall are both cast in place concrete, it is very annoying.

Room Bounding Structural Column Materials in Revit

I recently discovered yet another obscure, hidden away setting in Revit - when I was investigating the "Room Bounding" property of different elements.

It seems that some structural columns have a "Room Bounding" property - but not all.
This has to be one of the weirdest, arbitrary decisions made by the Revit programmers:

Material for Model Behaviour

Structural columns have a weird property - so obscure and arcane, not to mention hidden away.
'Material for Model Behavior'

This property that can only be set in the Family Editor – in ‘Family Category and Parameters’: ‘Material for Model Behaviour’.

It can be one of 5 settings, each of which enables different properties and behaviour in the model:

• Steel
• Concrete
• Precast Concrete
• Wood
• Other

Depending on which one you choose, it will enable properties in the family.

• Steel has Connection properties

• Concrete & Other have Rebar properties

 

These settings are hidden away behind the 'Family Category and Parameters' settings - in the project there is no way to tell which setting the family has, apart from the specific properties displayed.

You would have thought that this only affects structural engineers?

But wait.  It affects architects too . . . . .

• Concrete has ‘Room Bounding’ properties (it is the only one that does)

Why, oh why are wood and precast concrete not room-bounding?  There are a huge number of timber structures around the world that provide perfectly good enclosures.
Wouldn't it just have been easier to make all columns potentially enclose rooms, instead of hard-coding someone's bizarre ideas about how a building might work?

Room-Bounding

When working in a project, and you discover that a 'Room' is not enclosed when you expect it to be, this is one of many things to check.
There are some other quirky Room-Bounding behaviours in Revit, to be detailed later  . . .

• Room Computation Height

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