Changes! - Revit is not living up to it's user friendly name.

[3dway]

Hi Everyone.

We're doing a custom home. We had is designed and we've had to cut the area down. We slashed a foot out in three places along the longitudinal dimension, we slashed a foot out across the short dimension.

I had to bounce the plans out to autocad to finish them for a pressing deadline and since I'm new to revit, I couldn't finish things in time using revit.

To cut area in autocad I stretch the plans three times using a polygonal selection crossing and take a foot out each time.

I thought that it would make sense to send the plan back to revit and move/align whatever the walls to the autocad plan.

On the advice of one poster here, I had set up a grid line at outside face of stud and constrained the wall and foundation wall below to the grid line. This was supposed to let me move just the grid line and the wall moves with it's foundation wall below. I'm statisfied to go in an edit floor outlines ect after everything is generally in place.

Just about every time I try to move something I get a message that I cannot ignore about either it won't let me move the wall or it has to break all of the constraints an unjoin everything. It's getting to the point where it feels like it would be faster to draw it all over again.

I cannot do this. Part of what sold revit to us is that it's supposed to make these very kind of changes easier.

We hack areas down often. Clients always ignore our adivce on square footage and we end up cutting things like this when the price comes in. It so happens that this one was not for budget reasons and it was much earlier in the project. I'm chagrinned to thing how hard this would be if I were trying to hack area out of working drawings like ususal.

What am I doing wrong? What sort of setup can I do to make this sort of change possible?

[nsinha73]

We do the same type of projects in our Office. Just recently I had to cut 2'-0" off one building. And we made sure it was done in Revit. Because When you move a Wall, Revit makes sure your Foundation, Floor Slab, Doors, Windows, Roofs and Fascia Moves together.
And even Apart from that, It makes sure your interior Elevations, Sections and Elevations and dimensions are updated. Everything, moves by moving a single wall. ...what 2 secs most?....
Best advice, is to Stop 'Drafting' in Revit....Model it properly from the beginning. Revit is BIM, it needs best user Information to behave properly.
Our office practice is to make sure the Model is very very precise. Even though we have been only using it for 2 years, we never took a step back...now we are reaping the benefits of BIM.

my 2 cents ;-)

[aaronrumple]

Sounds like an issue of too many constraints.

I recommend not getting too ambitious with constraints and locks for this very reason. Unless you have a team of pro's working with you, the relationships can get out of hand.

Mostly you are probably looking at floors and ceilings causing errors. If their sketch changes such that they need another segment or they lose a segment - you'll get just the error you mention.

First clean up the constarints. Make sure you unlock dimensions that might interfear with the operation. Other "lock" constraints are more difficult to track down.

To avoid these sorts of errors you have a couple of options. First you can allways use move with a disjoin. This will break constraints and let the objects move without affecting other objects. The only draw back is you'll have to edit the floor/ceiling manually. And you will lose associated diemnsions.

Another thing you can do is cut the offending object(s) to the clip board. Then after you have made the adjustments - paste the objcets back in to the same place. Again you will lose dimensions associated with the objects. Not the whole dimension - just the witness line to that object.

[Scott D Davis]

Its hard to tell what may be keeping you from easily changing your model to cut down on area. If you can email me and we can set up a way so that I can have access to your file, I can take a look. Ultimately, it will come down to some Revit Best Practices that you can use on future projects to keep you from this "over constrained" situation.

[3dway]

We do the same type of projects in our Office. Just recently I had to cut 2'-0" off one building. And we made sure it was done in Revit. Because When you move a Wall, Revit makes sure your Foundation, Floor Slab, Doors, Windows, Roofs and Fascia Moves together.
And even Apart from that, It makes sure your interior Elevations, Sections and Elevations and dimensions are updated. Everything, moves by moving a single wall. ...what 2 secs most?....
Best advice, is to Stop 'Drafting' in Revit....Model it properly from the beginning. Revit is BIM, it needs best user Information to behave properly.
Our office practice is to make sure the Model is very very precise. Even though we have been only using it for 2 years, we never took a step back...now we are reaping the benefits of BIM.

my 2 cents ;-)

This is what I thought it would do except when I move a wall, the wall below, the floor etc don't go with it. Only things that are hosted by the wall.

My workflow is to draw the ground floor plan first. We always do this. The foundation plan follows the ground floor plan. Once the foundation plan is drawn, we'll round off the foundation dimensions to whole inches, then take the difference out of circulation space. This because formworkers are worse at math than any subcontractor and their work being accurate is the most important.

To draw the foundation walls, I've been laying down reference planes to show me where the outside face of stud is. Now that I write it, I expect this is where the relationships are being broken. Should I draw the foundation walls to an underlay of the gound floor plan, or should I draw the foundation walls where I can't see them on the ground floor plan and set the top and bottom constraints then just click the outside face of the ground floor walls and hope what's happening below works out?

Part of the problem is non continuous walls. If there's a cavity, I have three wall types along one length of wall a few wall joins and whenever I move anything the joins cause problems.

So generally, what is the best way to establish relationships between walls and other non hosted objects? By the way you draw it down? I thought that putting dimnesion constraints was the correct way because otherwise, how does the program know what I want associated with what? How does it know I want that closet shelf to stay agains the back wall and as long as the side wall no matter where I move the walls - what I get is walls that won't move because they're tied to the shelf, instead of the other way around.

What really needs to happen here is I need to get our CAD manager hopping and get user level access for us so we can get the white paper.

[DaveP]

Please forgive me if I sound harsh here, but that's a typical newbie mistake. We went through exactly the same thing on our first projects.
Dimension locks and Constraints seem like such a cool idea at first. "Great! I can make sure my corridor is always 8 feet wide." or "Wonderful. I can just Align this Wall with the one on the other side of the building and they'll move together!"

In reality, though, Constraints tend to cause more problems than they solve. Sooner or later, you're going to want to move something that's locked, and you'll have a h**l of a time figuring out where the lock is. Or worse, someone else will lock something down, and you end up moving something you didn't even know about.
After about our third project, we set the rule that no Walls should ever be Constrained. We never were able to track down why some walls kept moving.

That said, though, you can still shrink your projects when needed. The beauty of Revit is that you can select things in any View. I'd recommend selecting everything you need in a Plan View. Then - in a 3D View or an Elevation, see if you've missed anything. Eventually, you can see things in enough views to make sure you've got it all and THEN do the Move.

The things that will cause you grief are if you need to select things by using other than a rectangular box (fence tool, please?) and finding out that you moved that Walls, but not the Elevations or Sections.

Good luck. Hang in there!

[jarosa]

First of all i would take scott up on his offer.

Secondly, i'm a pretty new convert from acad and sometimes it gets tempting to want to just draw a 2d line and be done with it. Be patient. I try to constrain just the minimum...exterior walls to grid or reference lines. If you want you can take it a step farther...when creating floors/ceilings pick walls (not sketch lines) this should constrain them to the walls. then before you get to far test the model. Dimension the grid/reference lines then move the shell walls around and see if you are over constrained.

Other than that see below. HTH

Good Luck

http://bimcompletethought.blogspot.com/2007_12_01_archive.html

[3dway]

So I'm back to being confused. Should a foundation wall move with the ground floor wall or not? To me it should. And if it should, how do you establish that relationship?

[aaronrumple]

So I'm back to being confused. Should a foundation wall move with the ground floor wall or not? To me it should. And if it should, how do you establish that relationship?

ALL vertically stacked walls will move with each other. Somethuing to watch out for.
Yes, a underlay is the best way to place these elements. What you ave to watch for is something like:

| |
>| |
| |

In section.

What happens is newbie moves wall to correct place on floor 1. Then goes to floor 2 and wall is wrong. So he moves it to the right spot which drags walls on level 1 and 3 to a new location. Now he goes back to the plan 1 or 3 and moves everything again. You get the idea. Newbie spends the rest of the day moving walls back and forth.

Walls do not have to be constrained to do this. They auto-constrain just by the fact they touch....

To correct - either use a move with disjoin. Or use the align tool while looking at a section view.

[jarosa]

why not have all the shell walls "locked" to the grid/reference plane? In plan view lock the exterior core to the grid/reference plane.

Click Align. Select the grid. Then select the core. Then click the open lock to make it "locked". Do this only in plan view (foundation, first, second) so you know where your "locks" are. To test dimension and move the grid lines. Later you will dimension the walls without the grid so if you hide the grid in view you'll still have dimensions. Once i'm sure i have the shell the right dimension i lock the dimension of the grid lines so i don't accidently move the shell walls. Unlock this dimension to move the walls. It may be helpful to tile your screen and have the 3d model open so you can see if all the walls move.

Try a simple say 40'x24' basic model and get used to the way revit works. Once you are successful you'll feel better about the process.

John

[crispin.schurr]

I agree with DaveP's comments.

We design buildings with lots of irregular geometry / curves.
If we try locking / constraining every element of the project we end up hitting a lot of obstacles as elements refuse to flex - lots of frustration ...... and the design process just crawls along. We've found that we can only constrain everthing down for simple, rectilinear models, and not real architectural buildings.

After trying it both ways, we now leaving everything unconstrained.

Unfortunately this means that Revit will look for associations with anything nearby, and we regularly experience items (adjacent the geometry we are working with) jumping around as the design is refined. This occurs even if the rest of the model is completely pinned in position.

I believe this is Revits biggest flaw at the moment, and unfortunately you just have to keep checking and tweaking things as the model evolves.

Personally I would like to be able to manually turn off Revit's ability to try and guess constraints, and to leave everything unconstrained - at least then the designer is in complete control.

[mark.98140]

is it just me or is Revit seemingly defying it's intended use?... ie. revise instantly..hmmm.Archicad and even to some extent Autocad have a stretch polygon feature, that lets one select iirregular shaped areas and then nominate the stretch as a global or to be clearer ... 'total' stretch or move... that is; you get the choice to specify whether one is abandoning any constraints... so that one can do something as simple as stretch a building 1m longer... or shorter... in a selection set that is more than just a rectangle.. or series of rectangles. This is the way we work.. and it should be easily done... i don't use constaints .. but as mentioned revit has its own natural constraints via aligned walls, footings etc... so it will automatically complicate this simple task... surely we need a more intelligent and easy way of accomplishing this simple and often needed tool set..

just a thought.... and yes my work practices and up to scratch and i am not a newbie... yes i am a revit fan and not an archicad advocate... i just am pointing out a comon sought wishlist item... from our office :)

[sbrown]

As for the stretch command you do just what you described except you use the move tool. I'll go to a 3d view, orient to top, do a window around what needs to "stretch", then control tab back to the plan view and move it the direction I want, everything "stretches". As long as your roof and floor are created using pick walls models typically stretch very well.

[Mike Sealander]

Revit is a lot of things, but it's not user-friendly.
When I was nine or ten I read this article in Time magazine about how German Air Force pilots were getting killed by the score in their U.S-made F-104 Starfire jets. An American pilot quoted in the article said you needed the skill of a concert pianist to fly the F-104, and that's why the Germans were dropping like flies: the planes could do amazing things, but they were incredibly difficult to fly.
Well, that's pretty much my opinion of Revit. We do some amazing things in my office, and I'll never go back to AutoCAD again, but the learning curve never stops.

[twiceroadsfool]

In contast, Mike, i would say the learning curve of Revit is one of the easiest of the 3d Modl and Documentation platforms.

Sit with a team of fifteen learning Digital Project, and watch them (literally) throw a computer across a room after they draw two points, from points draw a line, from a line place a sweep... And then try to delete the points.

Revit is inherently more complicated than a 2d drafting program, but IMHP its just the nature of 3d modeling getting the OP down. In CAD, you could achieve a rectangle many ways, but the end result was alway the same, so- to an extent- how you got there didnt matter. In an object oriented live environment, that isnt the case... and the implications of the methods just happen to be biting right now.

Constraints are tough. In a project with more than a couple of highly skilled users, i tell people to shy away from them... Because its not just remembering what you constrained, its remembering what everyolne else did too.

As for making changed on the fly... I can lay waste in Revit, to the old seed we used to make changes... You just have to be organized, and know aead of time how the software "wants you to accomplish things..."

Youll get it, keep fighting with it...

[mark.98140]

As for the stretch command you do just what you described except you use the move tool. I'll go to a 3d view, orient to top, do a window around what needs to "stretch", then control tab back to the plan view and move it the direction I want, everything "stretches". As long as your roof and floor are created using pick walls models typically stretch very well.

i have to strongly disagree with this... yes in theory this is how you would handle a stretch in revit (and is how i do now), but it is a far cry from what i am talking about when i refer to a complex stretch achieved using a polygon stretch that enables one to stretch in random ways, not just simple rectangular selection sets... having been using revit for 6 years and other programs for over 20, i can say that to say revit is in this regard intuitive or user friendly is simply not the case... even doing what you say, any user would have to agree that a simple rectalinear stretch seldom goes smoothly or without pop up messages about unidentified links being broken or objects having to be deleted. This and other simple drafting tools are greatly needed... not that, as other have said, we would abandon revit.. it just can be much better

[dbaldacchino]

All the fencing tools and great selection techniques of CAD programs are not going to make these relationship errors disappear when you stretch a model. There are just a lot of spatial relations and "connections" that just don't exist in 2D CAD, so you just can't oversimplify and say that so and so tool will solve these issues. Can selection methods be improved? There's no doubt about that, but again, that's not going to solve the complexity of these issues in a 3D environment with so many objects having varying rules, behaviors and sketching methods.

[crispin.schurr]

I'm surprised the issues discussed here haven't been raised more regularly by users, as these are fundamental problems with Revit.

Are people just accepting that the issues they are encountering with geometry flexing uncontrollably is due to most users considering themselves learners?

The danger is that if you constrain everything, you just can't move elements anymore without getting lots of error messages - the design process crawls to a halt. If you constrain nothing Revit guesses the relationships between building elements and you get phantom changes to building elements that you thought you had pinned down.

This is just simply not good enough when consultants are liable for any mistakes in their documentation, and any rework required on site because the software package is doing some guessing for them.

Revit is fantastic software, but to some extent the constraints are built on some fundamental principles that don't exist in the real world - walls, floors and roofs are seldolm physically in alignment in real buildings, but are always offset at changing distances / locations for tolerances / weathering / architectural reasons etc.