Curtain Wall Post Summary

This serves as a quick summary of posts I've written here about Curtain Walls and their parts.

Updated: 01/13/2014

2013 Curtain Walls and Doors
2013 Curved Curtain Wall Edges
2013 Louver Curtain Wall Panel
2013 Family Templates and View Orientation
2012 The Missing Door

2011 Using Edit-in-Place on Curtain Wall Panels
2011 Curtain Wall Panel Edit-in-Place Update
2011 Ceiling Grid in Navisworks
2011 Curtain Wall Panel Edit in Place

2009 Curtain Wall Corner Butt Glazing
2009 Curtain Wall Louvers or How to Avoid Arrays

2008 Curtain Walls Fun Stuff by Others
2008 corner mullion Leg Calculator L corner
2008 Dept. of Unfair Tagging Mullions
2008 New Posts at HOK BIM Solutions

Using Edit Profile on a Curtain Wall

I recently responded to a post at RevitForum.org when a member asked about creating what sounded to me like a round top window using a curtain wall. I posted a couple screen captures and briefly discussed how they were made. This first one is a curtain wall embedded in a host wall followed by using Edit Profile to alter the sketch of the curtain.

This one is a bit more involved. I started with a single rectangular curtain wall and copied it to clipboard. Then I used Edit Profile to change it's shape. I then used Paste Aligned > Same Place to put the original curtain wall back on top of the first one. Using Edit Profile again allowed me to follow the edge of the first and design the second wall. Repeat the steps for the third and we have a curving set of mullions that are defined by three curtain walls that have complimentary sketches defined using Edit Profile.

I mentioned the use of the parameter Automatically Embed, a feature of curtain wall. The curtain wall types that are present in the stock templates vary but the simplest ones like Curtain Wall1 don't have the feature selected. If you sketch one of these walls over the top of another you'll get an error message.

I posted the following image because I thought it was worthwhile mentioning that the Cut Geometry tool the warning message references allows us do things like this too.

I also created a video that discusses these concepts.

Curtain Wall - Corner Butt Glazing Condition

I received an email from a client today asking about this situation and I thought it was a good opportunity to see if my voice would hold up for a brief video. I've been trying to shake a throat focused "cold" for a couple weeks now. Working through it hasn't helped clear it up.

I posted the new video about this HERE.

The essence of the tip is to create your own butt glazing "mullion" to stand in for the glazing compound that would really be there. You can duplicate the stock 5"x 5" Corner Mullion type, provide a new Offset parameter, define the Material as Glass, Match the left and right corner panel dimensions in the Depth 1 and Depth 2 parameters.

You place this mullion type at the corner of two curtain walls and you'll end up with something like this image.

If you want to, you can listen and watch right here below now.

Corner Mullion Leg Calculator - "L" Corner Mullion

Regarding defining a precise inside mullion width at corners of curtain walls: Craig Thomas with Leo A. Daly shared this concept with me. It goes something like this: (Craig writes)

I did some experimenting and found I could make the “L Corner Mullion” work to my satisfaction (your expectations may be different) for angled curtain walls. (Craig wants to define the inside edge exactly) This is what I found.

If you know the angle between the two curtain walls (A), the desired width of the mullion along the face (in my case 2 ½”) and ½ the frame depth (y), you can calculate how long to make each leg on the mullion (X”)(see image below – from Type Properties of “L Corner Mullion”). Here’s the formula:

X” = 2 ½” + (y * tan(90-(A/2)))


At first it may look like a lot of work, but with the calculator on your PC you can easily do the math. Then save the mullion based on the angle. In my example, I had a 7” deep mullion at 150°, with 2 ½” exposed in the corner.

I named it “L Corner Mullion – 150 degrees”.

Steve says, "You can enter this formula in the Leg 1 and Leg 2 field directly too! and make sure you use inches!!"


This is the result in the project:



Thanks for sharing Craig!!

I thought I'd "pile on" and add something to this concept. I built an annotation symbol that consists of parameters to enter the data required for the formula and does the calculation for you. Place the symbol next to your corner. Enter values, get the result. Then you can edit the mullion, create a new type and enter the values.
If you'd like to play with this you can download the file here!

Dept. of Unfair - Tagging Mullions

Mullions are not equal citizens in Revit. You can tag a curtain wall panel but not a curtain wall mullion. Specifically you cannot use the Drafting menu > Tag > By Category or Multi-Category. This means you can't tag them as simply as you can tag other elements, by creating a tag family and choosing one of the various Identity Data group parameters then tagging.

So what are your options?

You CAN tag a mullion using Drafting menu > Tag > Material. This uses the Description Parameter of the material assigned to the mullion. This may suffice...it may not.

You CAN Keynote a mullion using any of the three methods: Element, Material or User. Naturally this means you have to assign whatever you'd like to display in the tag to the Keynote value of the mullion.

The best solution would be for Revit's developers to promote mullions to equal status to other taggable elements.