Radial grids and walls, dimensions and sections

[Dimitri Harvalias]

I am beginning a project that deals with curved exterior walls and I am running into some questions/issues.

1 - Dimensioning of these radial grids is fine using a radial dimension but is there a way to dimension from grid 1 to grid 2?

2 - When sections are cut is there a way to align the section so it will be perpendicular to the curved wall?

3 - even if I can get the section aligned there is really no way I can see to dimension from the curved wall to another line. For example, to show distance from outside face of exterior wall to fascia for the roof overhang. In the Revit world nothing is parallel to anything else so I can't pick the curved wall.

This whole project is very complex and to build/model it in Revit is a piece of cake. To document it so the contractor can build it might be a different story and that has me very concerned.
Any suggestions or experiences out there dealing with radial grids would be helpful.
Thanks

[trent59822]

I have had this request into Revit for a while now. There is a work around though. What you could do is pick a grid line to draw a 2d line and then dimension the ends of the line. Hopefully, this will work for you. I'm hoping we can dimension parallel curved lines soon.

[Dimitri Harvalias]

Thanks Trent,

I have done as you suggest but I don't like the fact that when you pull the dimension off the points it is difficult to tell that it is a grid to grid dimension.
That only solves the simplest of the probelms. My big concern is being able to dimension on the sections.

[Wes Macaulay]

If you have a grid that emanates from the centre of curvature for the walls, you can attach a framing elevation to the grid. The section will be perfectly perpendicular to the grid. You still can't dimension very freely within this view tho :-(

[dfriesen]

Neat looking building there, Dimitri!

Looking at the gridlines, are you able to have one continuous grid line for the reverse curve?

[eldad]

I "LOVE" curved buildings (not) the last one I did was a bit of a nightmare when it came to dimensions, every curve end and start point needed to be dimensioned perpendicular to the grid, I used setout line from each point, that also made it easier for the builders reading the drawings.most of the info was on the plans thus avoiding too many dimensions in the sections...
Good Luck :)

[Dimitri Harvalias]

Daniel, If you think the building looks interesting you should see the site. Magnificent. I hope we do it justice with this project. In answer to your grid question, Revit can only create a grid line along one curve. You can create the grid with two curves but it will not have the same grid number. In the real world (the site, not the computer) radial grids are totally impractical so this is hardly a shortcoming.

Just to update those who might be interested...
The building configuration allows for the exterior walls to be segmented without any real issues. The location of windows and other elements that break up the facade permit the use of horizontal siding so the facets won't be too apparent. In reality this is the way it will be constructed (ie straight beams. not curved beams etc.) so it makes sense to draw it this way. I am using the curved grids only as a 'theoretical' reference and will be providing a layout drawing to the contractor with each grid intersection located from a common origin. This way the site can place these points and just connect the dots to form the outside walls, corridor walls and demising walls.

There is still some debate as to what walls need to be radially oriented and which can/should be parallel to others. For practical reasons washrooms will have parallel walls (offset from corridor and demising walls). The bedrooms will have two walls parallel, demising wall and the wall opposite.

My next trick will be sorting out the roof which will be a sloped plane supported by radially placed rafters exposed on the exterior soffit and the unit interior.

I am really hoping we can change the way we deal with contractors on a project of this nature. Orthogonal elevations are almost irrelevant because nothing is perpendicular to anything else so I'd like to use a great number of 3D views to help the contractor understand the design intent. The ability to cut sections at will without having to construct them by traditional methods will also save a bunch of time and effort. With camera and 3D views we'll easily be able to visualize some of the interior spaces (as much for the client's benefit as ours) to help us in the DD phase.
I can't imagine trying to attempt this without Revit. (Actually, I can, I just don't want to ;) )


Tons 'o fun!

[sbrown]

Do you want the arc length between 2 grids. If so you pick dim. select the arc length dim, the pick your curved wall, then the first grid then the 2nd and it will give you the length of that arc segment.

[Dimitri Harvalias]

Thanks Scott, but not what I'm looking for. I want to be able to dimension across the grids, so I can indicate the distance between grids.The only automatic alternative is to dimension the radius of each arc grid individually and then do the arithmetic.

I have come up with a simple workaround for plans. Since you can't dimension to the end point of a grid I used the pick tool to place a small arc segment drafting line on the grid and then dimension to the end point. Two problems/hassles with this method;
1 - unless you place the line and then offset, using the correct value, you can get an incorrect dimension because you are actually dimensioning the distance between the end points not between the lines
2 - it still doesn't solve the dimensioning issue in section

[Alvin_Alejandro]

You're right, What shall we do to this scenario?

[sbrown]

Not ideal but you could sketch a line from snap nearest on one grid, to snap perp on the other, then pick the line and make the temp dimension real.

[Parkinson]

This still doesn't seem able to be done ie dimension between radial grids.

[twiceroadsfool]

Im thinking a line based family would work for this... And be flexible enough to stay constrained if you move the grids, but i may be wrong. I think you could make a LBGM, that has references at each end, and dimension it in your project. Then the Family should flex if its locked to the grids, and the dim should go with the family.

This is a SWAG at the moment, as i havent tried it.

BTW, what are the grids made of? Last i checked, we couldnt have circular grids. I havent tried in 08, but are they actual "grids" or something else? And also, last i checked ieven if theyre perfectly perpendicular at the point the section is cut, they wont show up in section anyway, as they arent straight.

Did that change in 08? That would make my day...

[dbaldacchino]

I've worked in Revit since 8.1 and you could do circular grids then too.

It's very peculiar that you can dimension from a straight line to a curved line but not between two concentric arcs.

What I would do in a project is to use the pick tool to create a detail line and lock it to the grid. I would make it short so it's hidden in the gridline. One could use model lines if these dimensions are needed in more than one view. Then once I repeated this for all the grids I wanted to dimension, I would make sure to draw a line from the center of these arcs and trim the radial lines with it (so you get the true distance when you dim the endpoints). Then dim the endpoints and if the grid radius changes, the dim updates correctly.

Having said that, I agree that we need to simply be able to place a dimension between two concentric arcs without having to resort to workarounds.

[mruehr]

Hope i understood your problem
What about
draw a line with pick/lock on wall Center or Face
make radial dimension from the curved wall
draw a line from the center of radial dimension to where you want to have your section
trim the intersecting lines now you have endpoints to snap to Perpendicular to the wall
make section close to Setup line so it will align with it. keep both lines close together
you can move the section with the perpendicular line and the endpoints/dimension snap points will move with it.

[jeffh]

BTW, what are the grids made of? Last i checked, we couldnt have circular grids. I havent tried in 08, but are they actual "grids" or something else? And also, last i checked ieven if theyre perfectly perpendicular at the point the section is cut, they wont show up in section anyway, as they arent straight.

Did that change in 08? That would make my day...

You can have arc based grids and have had them for a while (not sure how long, but at least since Revit 8 ) You can't however do a compond curve as showon in Dimitri's example. The grid line can only contain 1 segment, either curved or straight. Otherwise it is considered a new gridline and gets a new label.

[twiceroadsfool]

Shows how much ive been paying attention, LOL....

[bclarch]

2 - When sections are cut is there a way to align the section so it will be perpendicular to the curved wall?
Draw a temporary wall in the location where you want the section to be with one end snapped perpendicular to the wall or to the center point of the curved wall. Create a section close to the wall and it should snap parallel to the wall. Delete the wall.

[steve922542]

Since this is an old thread, hope I'm not hi-jacking, but... Dimitri, how did you handle the unfolded, or flattened exterior elevations?

I only found one thread that discussed flat layout elevations of curved surfaces and there seemed to be some confusion about them and debate of their necessity. This project is a good example where such a drawing would be very helpful for design development and also for many of the trades downstream, particularly architectural millwork. Imagine ordering custom laid up veneer panels without flat elevations.

[Dimitri Harvalias]

As you pointed out Steve, this is a very old thread. Thanks everyone for your responses, even at this stage. I did come up with a variety of solutions for sections and dimensioning and the project is now about 75% built so it must have been enough information for the trades.

In the end the elevations were detailed as a series of separate elevation views. The 'curved' facades were actually faceted so this was a very easy solution. There is still no automatic facility for dimensioning to curved grids. Curved grid lines will appear in section views but only if the section view is perpendicualr to the grid.

[AP23]

The solution to this problem is quite easy. First of all, take a deep breathe and accept that Revit is made for boxy buildings. If you still want to create curvy buildings in Revit then you can export the views you want to dimension to AutoCAD and import them back into Revit. Autocad converts the edges of the wall faces to lines. Once the dwgs are placed on top of the floor plans or sections, you can dimension it by snapping or off setting to the autocad lines. Finally, just turn off the dwgs and the dimensions will stay in place. I've done this a few times and it works perfectly.

[Wes Macaulay]

Can only do boxy buildings? Not quite -- but in Dimitri's case it does require some linework to snap to, and use of specific tools to achieve Dimitri's goal.

[mruehr]

The solution to this problem is quite easy. First of all, take a deep breathe and accept that Revit is made for boxy buildings. If you still want to create curvy buildings in Revit then you can export the views you want to dimension to AutoCAD and import them back into Revit. Autocad converts the edges of the wall faces to lines. Once the dwgs are placed on top of the floor plans or sections, you can dimension it by snapping or off setting to the autocad lines. Finally, just turn off the dwgs and the dimensions will stay in place. I've done this a few times and it works perfectly.

Sorry i have to ...
Since my background is project manager and i spent an awful lot of time
with freedom of expression architects with
"it looks nice i don't care how you build it"Attitude.
Its fine to go wild on the drawing board but you think of the poor bugger out there who has to layout the Building. If you build a house that looks like a ship then its better to dimension it like a ship.
Revit as far as Dimensioning is concerned works right.On site dimensions taken of non perpendicular points need coordinates meaning a Point not a line.
this forces the Drafter to think and not just plaster the drawing with meaningless Dimensions Aka Autocad.
Well i like it the way it is.

[Dimitri Harvalias]

The building configuration allows for the exterior walls to be segmented without any real issues. The location of windows and other elements that break up the facade permit the use of horizontal siding so the facets won't be too apparent. In reality this is the way it will be constructed (ie straight beams. not curved beams etc.) so it makes sense to draw it this way. I am using the curved grids only as a 'theoretical' reference and will be providing a layout drawing to the contractor with each grid intersection located from a common origin. This way the site can place these points and just connect the dots to form the outside walls, corridor walls and demising walls.
!

I couldn't agree more mruehr!

As I pointed out earlier in the thread, the contractor was provided with a layout drawing showing all intersections of radial and curved grids as 'northings and eastings' from a common layout point. Worked like a charm although the surveyor had some issues with the project architect (no sense of whimsy those surveyor types :lol:).

In this day of too much work and too few qualified trades, I often expect my boxes to turn out like this building whether the dimensions are meaningless or exactly what the PM ordered :roll:

[timothy.porter]

Have you taken a look at Digital Project. You can create specific cutting planes which allow for perfect cuts through any geometry.

[Dimitri Harvalias]

Revit can create the cutting plane and the section is developed to a standard that is acceptable. The difficulty was that Revit doesn't have the ability to dimension to a radial object.
As for Digital Project, haven't looked at and probably won't in the near future because using Revit these issues are few and far between for the most part and I don't feel the need to go through the expense or learning curve at the moment.

[spectrumscope785606]

107731

HOW TO DIMENSION AXIS IN CURVE WALLS
- type DI, click ARCLENGTH,
- click the curve Reference line
- click each AXIS/GRID line one by one to continue
dimension in one group
- click outside to complete the command.

Hope this helps.