This introduction to Autodesk® Revit® is written for architects, engineers, CAD managers, and drafters who may or may not have access to the program. This will be the first in a series of Revit lessons that are tied in with AUGI Training Program (ATP) classes. If you want to learn Revit, stick with us. We are going to go from point A to point Z. For future exercises, you can download a trial version of the program, but in 30 days, you will not be able to save the model. If you are considering presenting the possibility of upgrading your company to Revit, we will discuss some of the points you will need to communicate to your principals and owners.
What exactly is REVIT?
If you are reading this, you are an architect, engineer, or drafter for any of the building disciplines. Or perhaps you are into facilities management. Could it be that you work for a construction firm or a design build house? Wait, I’m getting close... I can feel it. Do you use analysis software to design buildings under the new seismic codes? No? Okay, you create as-builts for institutional facilities. Missed again, huh? Sustainable design (green building)?
OK, OK, I’ll get to the point. Revit is a product designed to provide solutions for ALL of these industries. Have you ever heard of the term BIM? Come on, it was coined by Autodesk (or recently some people are claiming Dr. Seuss). Well, BIM is Building Information Modeling. This means that when I design a wall type and place it in a model, a detail is produced, a line to a schedule is added, a component is added to an analytical model, materials are added to a cost estimate, heat loss and gain calculations are altered, interior lighting studies are influenced and it even flushes the toilet if you forget! All right, so it won’t flush the toilet, but it sure will keep track of it.
Capturing work with Revit
Notice I have yet to mention 3D? Sure, Revit does incredible renderings and simulations. But please keep the 3D aspect in the back of your mind. Revit was designed to create the building model plan by plan, elevation by elevation, and section by section. No struggling with impossible 3D maneuvers that Frank Ghery would have trouble with. Instead, Revit uses 3D as an aid that you can put off to the side to help you draw. Or when you are designing a preliminary model, you ARE producing a perfect 3D representation that you can take to a planning board meeting to show the board. "Hey, look! At 5:00 PM the shadows cast here in lower Manhattan won’t cast a shadow on Battery Park." (I use this example, because the Freedom Tower was completely modeled in Revit). No AutoCAD® was involved in the making of this building.
The intro is done. Let’s take a look at Revit Building 9.1.
Views
Instead of using multiple files to compose a Revit project, the model in broken down into "views." Start replacing the word files with the word views in your mind. A plan is a view. A building section is also a view. Since we are working with a single model, multiple drawing files are a thing of the past (and it would be contrary to the goal of BIM). Right now, I am looking at the entire project. Granted, I only have five "views" open, but I can see a navigational breakdown of every view, just a click away. This is where the power of Revit first shows itself.
Project Browser
The project browser reveals quite a bit about Revit and how it immediately differs from AutoCAD. Instead of saving file after file in an often convoluted, never standardized folder structure, Revit uses ONE file. That's right, one file. Do I have to list the problems this eliminates? Pretend you are cleaning out your purse or wallet. Throw out that "nested x-ref" card; nope, don't need that. Design center, tool palettes, inserting blocks! How many times was that whole procedure reinvented?
As you can see in the image below, the entire project is visible at all times. Each view can be opened in its own window. The windows can be tiled. When a change is made to one view, that change is propagated down to the rest of the views. What is really nice is that when certain items such as floor levels are created, a plan will be made at that elevation from datum. The categories: Floor Plans, Ceiling Plans, 3D views, Elevations, Sections, Legends, Schedules, Sheet Families, and groups are all built in to Revit. You can’t add or delete any of these categories. This is a tough thing for some AutoCAD users to come to terms with, but it forces standardization. Revit becomes our CAD Manager. By the way, layers don't exist either.
Ok, by now I have probably furrowed enough brows and raised some practical questions.
What if the ONE file that my entire project is based on gets damaged or deleted?
Have MUCH fear. Come on, it isn't fool proof, but again, it's better than AutoCAD. Revit does NOT create a backup file nor does it automatically save. It does, however, prompt you to save if you forget. This prompting occurs at time increments that you specify just BEFORE you launch that command that causes the fatal error. Revit will create a backup file, but it is a full-blown copy of the original. You can specify how many additional backup files Revit creates. The default is three. No more renaming .bak to .dwg and crossing your fingers, or searching through the windows temp folder for an sv$ file. This point is almost moot, given the fact that I have never been able to crash Revit. It is extremely stable.
How can other people work on the same project?
There are two ways. My first choice is to use what's called "worksets." The concept is that a main file is saved to the current job directory on your network. This file is saved in such a way that it is considered the "central file" by Revit. Copies can be made of it and users can actually work on these files on their local drives. When they save the changes they make, they are prompted to save the changes to the central file. Can you think of possible problems? I can think of one. I’m resizing columns while somebody is MOVING the column line. This is avoided by using what is called worksharing. Certain people can have "administrative" access to specific items on the model. Certain people can be "locked out" of these items as well. Again, CAD Managers or project managers have ultimate control. This concept WILL be studied and taught within the AUGI HotNews series as well as within the ATP.
AutoCAD and Revit
Drawing (.dwg) files are as easily inserted into Revit as they are into AutoCAD. They can contain a link, so the concept of externally referencing a drawing file still exists and is very much the standard practice. Revit also is able to filter layers and control layer visibility states. Revit will also import the much beguiled .dgn (Microstation) file and can easily export to a .dwg and .dgn seamlessly. I recently visited a company that was convinced that one of its consultants was using AutoCAD to produce the drawings they were sending over. It just so happened I was at that consultant's office earlier that day. I still could not convince "company A" that "company B" used Revit Structure to produce the CAD files they were using as their overlays.
Many firms switching to Revit will insert all of their typical details onto a coordinated sheet. This alleviates many of the major concerns associated with being "stuck" in a new, foreign program, and allows for the most productivity in those early transitional stages. It is recommended, however, that eventually all of your company's details are converted over to the .rvt side of the playground.
Scale
How long will it take to change the entire plan to 1/8" from 1/4"?
A while Billy. It's going to take a while. I suppose you want to scale down all of the details too? Please get out of my office. Just... just leave.
Scaling is no longer a consideration. All of those conversion charts literally can be thrown out (OK, save one for nostalgia). Any text, symbols, or tags are automatically scaled down and repositioned with the flick of a switch. There are no complicated formulas. Your company does not have to pay someone to come up with LISP routines, templates, dim styles, text styles, and charts.
Creating Sheets
Title blocks can be created using old AutoCAD drawings. Each job has specific information about it, right? Job name, location, consultants... and the list goes on. You fill out this information ONCE. All title blocks will reflect the job parameters. Every elevation marker, section marker, callout bubble, and label knows which sheet its corresponding view is on. You can never have two of the same exact views on a sheet and you can never have a marker call out to the wrong sheet. If you change a page number, all of the reference tags throughout the entire project will change with it. It is impossible to break.
The project navigator will always be accurate. You can change the sheet number either here or on the title block itself.
Speaking of details, you can produce details just as accurately and aesthetically pleasing as you can in AutoCAD. If I change any element in plan, this detail will reflect those changes. There is not one single piece of "dumb" text here.
Oh, by the way, this model was created in Revit Structure, but I am presenting it in Revit Building. Revit Structure, Revit Building, and Revit Systems have absolutely no compatibility issues between them.
This is Revit. This is also the first in a series of learning modules that will take us through Revit from beginning to end. The lessons will be put under a microscope in the ATP as well. So I hope to see you in December and throughout 2007.
(Discuss this Article! in the HotNews Discussion Forums.)
Submitted by Eric Wing, who has been in the building, architectural design, and structural engineering field for 15 years and has been managing, teaching, and presenting Autodesk applications for 10 of them. Eric’s activities within AUGI include: ATP Director, Survey Manager, ATP instructor, HotNews columnist and AUGIWorld columnist. He serves as an Application Engineer for IMAGINiT, a large Autodesk reseller. He can be reached at atpmanager@augi.com
