SLOPED CEILING

[Doug]

Hi
I got a problem with a sloped ceiling -
its a 1/4 circle ceiling with an interior radius of 80' and thew outside radius of approx 100' - The problem - the exterior radius undulates or snakes with mutiple curves.

The interior radius height is a constant 9'-0" and the exterior (undulating) edge is a constant 10'-8"

Any ideas to accomplish this? I am using 2011
:?:

[Doug]

I can model this using a roof, Modify Sub Element Tools - (Why can we have the same tools in ceilings?) Only problem is non of my ceiling based items work with a roof as a ceiling!

Any ideas?

[mthurnauer]

I was able to make your shape as an in-place family. I made it as a blend with the bottom profile as the wavy edge and the top profile as the upper radius. For both profiles, I offset the finished edge outward by a foot so that I could form a closed loop. I then had to create a void at the bottom and top edges to trim the shape. The ceiling can host objects.

[cliff collins]

Could you create the ceiling shape in an RCP, then use a slope arrow to set the upper
and lower heights?

cheers

[Alfredo Medina]

Could you create the ceiling shape in an RCP, then use a slope arrow to set the upper
and lower heights?

cheers

Wow! That is the easiest solution! Excellent!
A ceiling entity made with a sketch, with a 5 degree slope, with the slope arrow.
I had thought about making this with solids, similar to what Mthurnauer did, but with an extrusion. I never thought of this easy solution. Great!

[cliff collins]

I'm not sure the slope arrow would work for controlling the EXACT height at the undulating/freeform edges--it may have to be built with several smaller ceilings
and then joined.........

But in most cases the slope arrow method works well for sloped ceilings.

cheers......

[Alfredo Medina]

Yes, it will. The difference between the inner arc and the outer curvy edge is 1'-8" in height. With the radii mentioned, the slope is 5 degrees. The slope arrow will be set for this slope. It works.

[cliff collins]

excellent!

cheers

[Ning Zhou]

besides using Slop Arrow, you can also use Defines Slope, similar to footprint roof.

[Alfredo Medina]

besides using Slop Arrow, you can also use Defines Slope, similar to footprint roof.

Where, exactly?

[Ning Zhou]

select an edge in sketch mode, then check "Defines Slope".

[cliff collins]

see attached.

cheers

edit: RAC 2011

[Alfredo Medina]

Hmm.. "Defines slope" doesn't work in this case, because in the sketch of a ceiling with that shape, Revit doesn't allow me to apply a "Defines slope" mark to the inner arc. Only to one of the straight segments that connect the inner arc with the curvy exterior set of arcs. Therefore, the slope will be in the wrong direction, since the slope is applied perpendicular to the edge. I just tested it, applying 5 degrees of slope to one of the sides, since I can't do it in the inner arc, and the result is that the difference in height between the inner arc and the outer set of arcs is 8'-4", which is a lot more than the 1'-8" specified for the exercise.

[cliff collins]

Slope arrow wins!

cheers

[mthurnauer]

I tried the slope arrow and I don't see how that works. The undulating edge is not at a constant height as requested.

[cliff collins]

Yes--

I was suspicious of that too.

Alfredo?

Looked like he had it solved w/ slope arrow?

Maybe post an example.

cheers

[Alfredo Medina]

Mthurnauer wins!

Initially I liked Clff's solution because it was simpler, doing a sketched ceiling and a slope arrow from center to center, and I initially thought I had done it right, but now, double checking, I see that it is not possible with this method to meet the conditions of the exercise. Mthurnauer's is the correct solution.

[cliff collins]

Well, it was a good try-------

whose idea was it to do those darn undulating edges, anyway?!!! jokes

cheers

[Doug]

I was able to make your shape as an in-place family. I made it as a blend with the bottom profile as the wavy edge and the top profile as the upper radius. For both profiles, I offset the finished edge outward by a foot so that I could form a closed loop. I then had to create a void at the bottom and top edges to trim the shape. The ceiling can host objects.

Thanks! this works BUT it is alot more work than creating a roof. If we could just get the same functions roof creation has in the ceiling creations.

[r.grandmaison]

Is this what you wanted? (Note: I didn't try to keep the undulation even, just threw in a very loose spline to get the point across.)

[Alfredo Medina]

Wow, a 3D Dwf! COOL!!

The specs of the exercise call for a constant height at the wavy edge. Therefore I think Blend is the only operation that can keep that edge at a constant height. How did you do this one, Bob?

[r.grandmaison]

Wow, a 3D Dwf! COOL!!

The specs of the exercise call for a constant height at the wavy edge. Therefore I think Blend is the only operation that can keep that edge at a constant height. How did you do this one, Bob?

DOH! I missed the part about the outside undulating edge needing to be a constant elevation as well- that'll make for a very difficult ceiling to build in the real world- lots of undulating surfaces!Hmmm...how about this method: Build it in AutoCAD and import it! ;) It seems to me a blend would be the best bet though. Top is defined by the undulating edge at a constant elevation and the bottom by the arc at a constant elevation too.

And, as for the 3DDwf Alfredo, and for anyone who hasn't done so, exporting to dwfx in 3D is a terrific way to share information. Much more valuable than a static jpeg screen capture.

(My first was just a simple revolve with a void used to create the undulation...My second attempt is much more than that...)

[Doug]

Not so hard to build - harder to model using the tools we have. Actually it is a curved undulating cantilevered balcony edge that looks over a lobby and out to a curvered two story glass curtian wall. The ceiling is attached (@ 9' ) to a interior wall is a curve that matches the exterior glass curtian wall - the udulating blacony edge (@10'-8") is held back to the about 1/2 of the lobby is 2 story. We want the balcony edge to have a uniform thickness

It was easy to do with the roof commands - All I want is the same commands for the ceiling design tools or away to make a roof a ceiling.

[cliff collins]

How about a Floor, since that is actually what it is? Instead of a roof or ceiling.

cheers

[Doug]

It is a ceiling under a floor, but it would make it fun to walk on.

This what I modeled using the roof commands

[cliff collins]

Understood. Looks good.

However, could this not be done with a Floor Assembly, which includes the "ceiling"
part underneath?

cheers

[Doug]

Attached is the model I am trying to make. It was easy using the roof tools but impossible just using the existing ceiling tools.

I still would like to have lights and HVAC "stick" to the ceiling. Right now I am going tpo fake it by placing another "flat ceiling" into the midel so I can have all of the equipment show "correctly"... at least where it belongs.

Hey Factory... how about the same tools for doing ceilings as roofs?

[Doug]

Understood. Looks good.

However, could this not be done with a Floor Assembly, which includes the "ceiling"
part underneath?

cheers

Am I missing something? How can I get the floor to be flat and the ceiling to slope? I just tried that... how do I get the ceiling to slope instead of the floor?

[cliff collins]

Flat floor as separate sketch on top.

Sloped floor below, which has the "ceiling" material built into its lower surface.
Floor tools have slope ability sim. to roofs.

Join geometry.

Use face-based fixtures to attach to "ceiling" part of the lower floor.

But it's a workaround--I agree it would be great if ceilings had the same controls as roofs/floors.

cheers

[Doug]

That leaves me with the same problem - no any to attach ceiling based items to the "ceiling"

Tools please....

[cliff collins]

You can use face-based families.

cheers

[Doug]

oh GREAT!
Time to redo all my families!

[twiceroadsfool]

We've been writing long tedious emails to Autodesk about this very issue:

The line between how to MODEL an object, and WHAT THE OBJECT IS, needs to be definable by US.

Thing of the modeling METHODS we have:

Repeatable element (curtain system)
Draw-by-Path (Walls)
Draw-by-Path-Sketch (with rules)-Current railings/balusters
Draw-By-Sketch (Floors),
Apply-By-Face-to-Mass (A few things),
Place-prebuilt-object (Components)


then we have objects themselves. Really, "Walls, Floors, Ceilings, Roofs, etc" should all be one thing called Assemblies, with a subdivision for use, that we can define. Id love to draw a mass, for a building where the walls wrap and turn in to the roof. Then apply "assemblies" to the outside. Grab one and switch it to a roof, and grab one and switch it to a wall.

This would grant us: Ceilings by faces, multi sloped floors, system families built as out of place families (very useful). It would also grant us parameters in actual system families without needing to kludge together everything with mass families, something that was hugely beneficial about Digital Project.

There isnt time to write out the full diatribe on the concept ,and its a bit fruitless, because it is too big of a shift in the function of the program for it to ever be considered. But its what we need. Everytime i consider (and i say consider, because we dont do it, as an office) using the wrong Revit tool to make an objet, because one modeling TECHNIQUE works better than the CORRECT one, i get back to this concept...