Adaptive Component curtain panel caclulates incorrectly area in schedule

[Anonymous]

That basically says it all.  I did a simple search for similar issues, but am finding only results where the computed area was half of what it should be.  In my case it is weirder: the calculated value of the area paremeter is a bit more than 150% of the actual value.  The latter is derived by creating an area shape based on the face. 

Any thoughts?

[Alfredo_Medina]

The title of the thread "basically says it all"? Not really.

For a question of this kind, you need to provide either an image, or the Revit family, or both. It is not possible to solve these issues by just reading a description. 

[Anonymous]

OK, mate, relax.  I was first trying to find out if someone else has had the same problem and a stock solution existed.  Here it is, for your viewing pleasure:

 The family in question is based on an adaptive component used as a repeater along a divided surface.  Here is a view of the AC curtain panel:

It has been used to simmulate a puzzle piece installation, as a panel-repeater within a divided surface:

I created a curtain panel schedule with the intention of calculating the panel areas and throwing a rough $ number/S.F. for budget estimating.  When verifying the automatically generated area take-offs, I noticed a severe discrepancy b/w the area of the filled region I generated mimicking the outlines of each test panel, and the are value of the respective panel in the schedule.  The calculated value is always roughly 1.5x the area of the check filled region.

The file is attached.  Any ideas what's going on?

Thanks,

Raffi

[chrisplyler]

Is that split surface just as wavy in the third dimensions as it is in the two dimensions we can see in your picture?

Is it wavy enough that the actual surface area of each panel might be close to half again as much as the panel's projected area (which is all your getting from a detail region)? I doubt it, because the average angle of the waviness would need to be roughly 48 degrees to approach a 50% area increase. And for the average to be 48 degrees...well, I don't imagine you're designing accordian baffles.

It was just off the top of my head. I don't have any knowledge about the inner workings of Revit's split surface area calculation methods.

[Anonymous]

chrisplyler, the divided surface is completely flat. For a moment I thought, that the area being calculated is the rectangle that each piece can be inscribed in... close, but not quite.

[Alfredo_Medina]

The area of a surface of a flat curtain panel is reported as half of the area. I think Revit asssumes that the panel will have some thickness, but if the panel is flat, the area reported in the schedule is half of the area of the surface. In your case, it reports more than half because your family contains two surfaces instead of one. So, simple solution is to eliminate that extra surface, and then multiply the area by 2 in the schedule. If you create, instead, a solid form with some small thickness, even if the thickness is very small, then you will have a much more accurate result, but you have to remove the extra surface anyway.

[Anonymous]

Alfredo,

If you had opened my family you'd know that I did exactly what you suggested in the second part of your post.  My AC panel IS actually a solid form with a small thickness.

So, I'm afraid that's not it.  And why did you bolden the word "flat".

Cheers,

[Alfredo_Medina · Accepted solution]

I did open your curtain family. By the way, I don't understand the reason for having so many elements. (32 reference points, etc...)

You don't need more than what is shown in this image, below: 8 adaptive points, 1 "other" which is the surface, 4 lines, which mark the boundary, and 1 divided surface (this divided surface is the key to fixing the issue with the value of the area).

As you can see in this other image, this simplified version of the panel, without thickness and with a divided surface, schedules the area correctly:

[Anonymous]

Alfredo,

Thanks for the analysis.  You are right that the adaptive panel is a bit convoluted.  The main reason for that is the need to account for a joint gap between the panels. If you figure out a way of doing it simply, PLEASE, let me know.  I am not the savviest modeler of adaptive components, and I can always learn new tricks. 

So it is this divided surface that sets everything straight, eh? How about it!  Good one; thank you!

Cheers,

RT

[chrisplyler]

Even so, don't use more adaptive points for the form. Use regular reference points, each hosted on the x/y plane of the nearest adaptive point and offset inward. The pic below is just an example. Of course you need to set up constraints to keep the gap correct as desired. Spline four reference lines through the regular points as I've shown, then make your form on those four lines.

[Anonymous]

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@chrisplyler wrote:

Even so, don't use more adaptive points for the form. Use regular reference points, each hosted on the x/y plane of the nearest adaptive point and offset inward. The pic below is just an example. Of course you need to set up constraints to keep the gap correct as desired.

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So, chrisplyler, now you have to show me how exactly to keep the joint gap constant and parametric on a completely freeform panel, and you will have found yourself a fan.  "The pic below is just an example." just does not cut it for me: still finding my way through the parametrics in Revit.

Cheers,

RT

[chrisplyler]

Okay, hold on, it's going to take a couple of minutes for my short video to upload. Actually it's longer than it needs to be, because I went ahead and constrained the whole thing. You will get the idea after I've done one corner and one side.

[chrisplyler]

Here you go.