Scheduled Wall Areas don't match

[Andre Baros]

We are doing some VE on a project and wanted to reduce the amount of curtain wall... so we did 3 schedules.

A wall schedule of curtain walls. 1683 SQFT
A panel schedule of glazing panels. 2050 SQFT
A material schedule of curtain wall glass. 3841 SQFT

Not only are the three different (they should be) but the schedules are reporting more panel than wall, and more material than either (but not double or close to double)

In a test project I layed out a few of the same walls and the numbers made sense, but in the real project they don't.

SO, is there a way to hide/isolate curtain walls (not just the panels)? Any other ideas on how to trouble shoot this?

[Andre Baros]

BTW, I already tried doors in the curtain wall. If I change doors or spandrel panels to glass, the total glazing panel area goes up but the curtain wall number stays the same.

In the test file, an 8'x10' wall with glazing panels and mullions reported 80 SQFT of wall and 71.5 SQFT of glazing, which makes sense.

[mcloer]

I noticed this a while back as well. We needed to confirm a quantity of precast concrete in a tilt building. We did a material takeoff in Revit and then a polyline in AutoCAD. The polyline was almost exactly half of the number we got in Revit. Similar to what you are getting.

Revit must add both sides and the perimeter when it calculates material area.

[todd.69291]

We found that we could not use material take-offs for glazing or any other extruded part. What is a curtain panel? Extrusion. Extrusions have how many sides? 6. If all six sides are "glass" material and are calculated then it screws up you your material take-off schedule.

This will apply to anything that is extruded.

[dbaldacchino]

Hmmm so you're saying that it takes the surface area?! That's just not right. I haven't experimented with material take offs yet, but I'm going to right now.....

[dbaldacchino]

Ok, you're right. In the case of glazing, the material area reports the surface area, as if the material was "painted" on. The Area parameter only reports one face, so in case of extrusions you canot use the material area. I find it odd that for walls, there is no height field that can be reported in a schedule. Also, why isn't it possible to calculate totals on the Area field?

Andre, have you checked wheter you have any design options in the project with curtain walls in them? How about liked projects with more curtain walls in there? If the schedule reports elements in linked files, that could account for the discrepancy. I would also review the warnings to see if you have elements pasted on top of each other, which would double up the elements in the schedule. You could also try selecting all instances, isolating those elements and deleting one by one to see if there's duplicates. Or you could cut them and paste them into a new project to see if the reported areas are the same.

[Andre Baros]

9.1 BTW seams to clear up the material take off... it's not longer counting all the extra faces.

But that doesn't help here. Ignoring the material schedule, I still can't figure out the panel vs. wall thing but will try copying everything to a new file today to narrow it down.

[Andre Baros]

Ok, we solved it. Double mullion lines were creating double panels. The curtain wall area was correct (and in 9.1 the material area was correct) but the panel schedule was counting/showing the double panels. Revit warns you about this when you create other types of double elements, but I think the double panels were an error so there was no warning.

[robert.manna]

So wait, you had two panels on top of each other? Was this a software error or user error? Just curious, we have not upgraded yet to 9.1.

Thanks,
-R

[Andre Baros]

This was in 9.0.
Here are the facts:
Curtain walls were changed from one type to another.
Grids were adjusted and grid lines ended up on top of each other as things moved around.
A schedule was made showing more curtain wall panel area than curtain wall area.
The double grid lines were deleted.
The panel area schedule came back to a logical relationship to the curtain walls (about 8% less which makes sense taking into account doors and mullions)

My conclusion is software error though I haven't taken the time to reproduce or report the issue yet.

I opening the file in 9.1 to see what would happen but we're not switching until later in the week when some big deadlines pass for job's in 9.0, when we'll all switch together.