Revit 2016 R2 - Changes to Underlay

They've reconfigured the Properties Palette and changed how they describe and provide access to the Underlay concept.

As you can see above, the Underlay concept now has its own Group Header in the Properties palette. They've renamed the Underlay parameter itself to Range: Base Level. The new Range: Top Level is a read-only value that just reports the next level above the Base Level. That can be helpful when it isn't the one you expected, for example when there is an intermediate level for a stage .

Keep in mind that if a view is created for a level we can't prevent that level (like Stage above) from being the next one, the one that appears in Range: Top Level. I think it could be better if a Level's Building Story parameter could influence this condition so a view could exist for the level but not be factored into the Underlay's display process, allowing it to skip past or ignore the Stage level.

The Underlay Orientation parameter kept its name but the words used to describe its choices are now Look up and Look down. The plainer language seems to help people understand what Underlay is really doing. At the very least Look up is more accurate than implying it is really generating what we have learned is meant by Reflected Ceiling Plan.

Also very worthy of a mention is that new plan views have their Underlay - Range: Base Level assigned to None instead of the Level Below like in earlier versions.

Hmm, writing that last section, it occurs to me...this feature used to just be called Underlay, a parameter AND concept on its own with a second related Underlay Orientation parameter. Now we have a concept of Underlay with three parameters.

Experienced users will now confuse new users by asking them, "What's the view's Underlay assigned to?" or telling them, "You need to change your Underlay setting."  ...ah progress...

Oh, and Hat Tip to Niklas Strannefors, an Autodesk Application Engineer in Sweden, for prompting me to write about this subtle change.

Scope Box Issues with Disciplines

When we assign a view to Mechanical, Electrical or Plumbing disciplines a Scope Box gets treated as an underlay element and its graphic display is also affected. This image is of a mechanical view and a scope box, only two sides of the box are visible (it's been like this since 2012 at least). Since it is regarded by Revit as an underlay element if I choose to disable the Select Underlay Elements option (new in 2014) I can't select the Scope Box either.

There isn't much we can do to counteract this graphic quirk except to deal with scope boxes in views where they aren't graphically harmed. Most of the time people want to hide scope boxes faster than a litter box when guest arrive. For offices that don't show a scope box in printed documentation it isn't an issue. If you really want to show it then it might be necessary to create an annotation symbol or detail component that you can use to compliment the Matchlines that are usually associated with scope boxes.

Keep in mind that each Scope Box has a Edit button for Views Visible (button is in the Properties Palette).

This dialog governs which views the scope box will be visible in or not. If you find you can't see a scope box in an elevation for example then double check these settings. You'll probably find that it is set to be invisible in the view.

As mentioned in the first line of the dialog in the image, Scope Boxes are automatically visible in 3D views and in other views where they (the scope box) intersect the view's cut plane. This changes dynamically, if the scope box is altered so it comes into contact with a view's cut plane it will change from Invisible to Visible without any additional effort on our part. We can use the dialog to force either condition to be persistent however.

Fittings Do Not Look Right

A troublesome thread popped up at RevitForum.org the other day and DMapes came to the rescue. I haven't encountered this peculiarity before, and now that I know about it it's a bit surprising that I haven't. I guess I've just been lucky.

When you use the Underlay setting in Revit MEP you run the risk of altering the way your pipe fittings (duct fittings too in views using Detail Level: Coarse) scale and/or look. Here's a good and bad side by side.

The pipes on the left are good but those in the view on the right are smaller and halftone, as a result of using the Underlay setting.

Set to None the fittings look correct, but using the same level the fittings are associated with as the underlay equals sadness. It doesn't seem to mind if you use other levels as the underlay though. Careful with your underlay!

Revit Links as Underlays

From Autodesk Wikihelp for Revit 2012.

Using a Revit link as an underlay can be a common workflow for architects and especially for engineers. A link can be set to Halftone to distinguish it from the main model, but new work (model lines, for example) can still end up being obscured by geometry (walls, etc) in the link--making it difficult to see what you've drawn. Revit 2012 solves this problem:

• Open your Revit project.
• In the Insert tab, click Link Revit.
• Navigate to the Revit model you would like to use as an underlay. Click Open.
• In the View tab, click Visibility/Graphics (or type the keyboard shortcut “VG”).
• Click the Revit Links tab.
• Next to the Revit link that you just inserted, put a check in the Underlay checkbox. Click OK.
• The geometry in the link will now be halftone, and more importantly, it's a true underlay: the link geometry will not obscure new lines and edges

I have the following comment on this new setting:

Cool but, keep in mind that this does not address the selection order experience we have unfortunately. I'm describing the situation that a linked file is "selected" by the pre-highlighting before native RST or RME elements. This means that Revit "sees" the Architecture model before it sees the RME user's duct (assuming the view is assigned to Hidden Line).

Ideally a link should take a "selection back seat" to elements that are native to the active project file.

Spot Dimension and Underlay

Hiroshi Jacobs brought this item to my attention the other day. He also shared with me that he's been accepted to the Masters of Architecture program at Harvard!! Attaboy Hiroshi!! He currently works at RTKL in DC. Here's the issue.

There is currently a “bug/issue” (2009/2010) when you combine the use of these two features. First of all when you use the underlay feature you get to choose which Level of the project you’d like to add to your view as an “underlay”. The spot dimension tool lets us identify a point elevation or point coordinates on an element in the model.


In the image above you can see that combined they can have an undesireable result. The conditions for this are using an Underlay of a Level ABOVE the level of your current view and having a floor above in the same area as the intended location of a Spot Elevation.

When you place the spot dimension in an area where this underlay doesn’t compete for attention you get normal results. However when you put the spot dimension in an area where the underlay and its floor are present Revit will identify the spot elevation of the underlay, not the floor that it "should be" paying attention too.

Does tabbing permit you to choose the correct element? No it doesn't. If you use the Underlay Orientation: Reflected Ceiling Plan the Spot Elevation tool works as "expected", it does not "see" the floor above, if that makes any sense at all since the floor should be more visibleish? I'm confused...

Since I brought it up what happens when you switch between Underlay Orientation: Plan and Reflected Ceiling Plan? Let's see, watch the Spot Elevation that displays both top and bottom values for the underlay floor above. First with Underlay Orientation set to Plan.


Notice the values...now compare with Underlay Orientation: Reflected Ceiling Plan.


Does it matter if it is a floor or roof? Does the same thing for either. Interesting that the elevation values change depending on the Underlay orientation, increasing with the Reflected Ceiling Plan selection. Keep in mind that the floor is at Level 2 which is just 10'-0" above Level 1. I could understand the top vs. bottom display values switching places in the tag with the orientation change but not the elevation values becoming something they aren't.

Boiled down the underlay is “more important” than the current level’s elements when using the Spot Dimension tool. Keep this in mind when using the Spot Dimension tools and using an Underlay.

One more for the road: Spot Dimensions don't like Model Graphics Style: Wireframe. The tools won't "see" the surface unless you change to one of the other choices like Hidden Line. You can switch back to wireframe afterward and the values will stick. This is from an earlier "stump the chump" question and the answer.