Wednesday, March 27, 2013

Quick QAT






A quick tip to speed up Revit work flow is to move the Quick Access Toolbar below the menu ribbon.

It should probably be there by default. I've noticed that many users overlook it at the top. To move it simply select the option at the bottom of the drop-down.

The Out-of-the-Box commands are as shown.








Add almost any command to the QAT by right-clicking... 




My personal favorite is to place the Type Selector drop-down on the QAT. Because the interface is context sensitive, alternatives to the object currently selected are shown immediately above the work space.

For the Playa Vista project described in the previous post, which was heavily dependent on Design options, placing the 'Pick to Edit' tool on the QAT was an incredible time saver when working among the various options in the model.


Sunday, March 24, 2013

Design Options & Groups


I am working with two teammates on a project for Brookfield Homes, the unequivocal leader among home builders who have embraced Building Information Modeling.

My colleague Louis Navarette is responsible for the development of Brookfield’s BIM Guidelines, families and template files which are provided to the architects and engineers who serve them. While the performance guidelines are very strict, specific methods are at the discretion of each designer.

Exterior Styles
The Playa Vista project consists of six four-story buildings - three dwelling levels over a garage level. There are two different building configurations. Four of the buildings contain six dwelling units; there are also two "tri-plex" buildings, which are derived by removing three smaller units from the larger building, while maintaining the main lobby and both exit stairs.

There are also two separate exterior treatments – A & B. Some exterior elements are shared by the two larger buildings only (6A & 6B). Other elements are shared between the larger and smaller buildings of the same style (3A & 6A). It was apparent from the beginning of the project that Design Options should be employed.

Design Options in Revit is intended for the depiction of several alternates or variations of a base model. The Design Options interface manages the display of the model based on the selected option. Only elements that change are placed into the option. Objects that occur in all three buildings are not duplicated – they reside in the “main model”.

Exterior Groups
During the course of our work, it became apparent that, for the most efficient modeling process, elements that were shared by two of the three options could be placed in Revit groups. When the group is edited, changes are automatically propagated to both versions, eliminating duplicate effort while insuring that design continuity is maintained.

Interior Groups
While there are three exterior options, the interior of buildings 6A & 6B are identical. For further efficiency, we decided to place the building's interior components (partitions, doors, plumbing fixtures, etc.) into a separate design option. Interior components that are identical from floor to floor are also grouped so that interior changes are also automatically propagated throughout all floors and styles.

When Design Options are activated, an additional tab is displayed in the Visibility/Graphic Overrides dialog. When set to Automatic, the model view displays the active option. For ease of editing, the template provided by Brookfield contains Working Views that may be pre-set to the desired combination of options.
There are two built-in filters to aid working with Design Options. When 'Main Model' is selected, individual elements within an option may be modified by unchecking the box labeled 'Exclude Options'. 
When a Design Option is active, elements in the main model may be edited by unchecking the box labeled 'Active Only'.
With a team of three on the project, the work flow was uncomplicated. Typically it was one person on the interior, one on the exterior, and one in a separate Composite Document file. Overall I am very satisfied with the methodology that evolved for this project, and intend to use it as a prototype for the next one.

Thursday, February 21, 2013

KMN

I work for one of the most prestigious and stable architectural firms in Orange County. I am the staff Revit guru, a position that allows great freedom and flexibility in determining how I approach my work. Currently, I am working with two other team members on a multi-family housing project for Brookfield Homes, a leader among home builders who have embraced Building Information Modeling.

We have two or three weeks remaining before the first CD submittal, with a lot of annotation and detailing still to to do. This is our first Revit 2013 job. Our client has expressed a desire to move to the built in keynoting system; previously we used generic annotations and note blocks. We are using Steve Faust's Keynote Manager on a 30-day trail, while waiting for approval on a site license.

In spite of all these conditions, when my project manager approached me yesterday with a request to use "dumb keynotes" as in CAD, I actually agreed!  I was immersed in another aspect of the project, and had not really considered the problem. I even created an instance-based symbol to be used in conjunction with blocks of text. Near the end of the day, when I paused to consider my accomplishments, I realized to what I had agreed. My first reaction was "KMN"

As with many firms in the housing industry, most of the work here is still being done in CAD. I recently I made a presentation to the staff here, extolling the benefits of BIM. which was entitled, "It's Not Rocket Surgery".

I quickly went to work, importing some notes from previous projects into the new keynote text file database. This morning I showed it to my PM, who is now on board. When he said, "I didn't know where to start" I realized I had failed to give the proper level of support for a new process.

Monday, October 22, 2012

Reality & Illusion

In the West (and I assume throughout the U.S. and elsewhere), where wood frame construction is dominant, these standards apply:

Standard length for 9 foot (nominal) studs is 104 5/8" or 8'-8 5/8". With top and bottom plates added, the standard plate height should be 109 1/8" or 9'-1 1/8". This allows for approximately a 9 foot clear interior ceiling height, depending on the finish.

For engineered joists, the actual size of the TJI-12 is 11 7/8", while the TJI-14 is actually 14".

Using these values, the top of 3/4" plywood sheeting will be 10'-1 3/4" for the TJI-12 system; and 10'-3 7/8" for the TJI-14 system. Roof plate heights for the two systems and 19'-2 7/8" and 19'-5" respectively.


In CAD, where accuracy is often pushed aside for expediency (because it's so inefficient?) these values have been "leveled off" to 9'-1", 10'-2", and 19'-3".

Also in CAD, reference values from finish floor are rarely given. The plate to sub-floor dimension is also excluded. The logic (?) being that at the start of the job, the floor assembly depth is unknown, and CAD must be protected from the demand for changes, where it is extremely inefficient.

When modeling with Revit, the best practice is to use actual values whenever they are known. There are no "unknowns" in a Revit model. The model is a record of all the information gathered about the building being designed. What better place to record those decisions accurately than in a Building Information Model?



Practitioners who wish to see no "differences" between CAD and Revit may set the dimension tolerance "to the nearest inch" and exclude the values from the level annotations.

There is no substitute for accuracy. 
When using Revit, do not attempt to substitute an illusion for reality.


Monday, October 8, 2012

Are We Men (and Women) or Are We Monks?


From Wikipedia:
The at sign or Astricks @ is also commonly called the at symbol or commercial at in English—and less commonly a wide range of other terms. The fact that there is no single word in English for the symbol has prompted some writers to use the French arobase or Spanish arroba—or to coin new words such as asperandampersat—but none of these have achieved wide currency.
Originally an accounting and commercial invoice abbreviation meaning "at the rate of" (e.g. 7 widgets @ $2 = $14), in recent years, its meaning has grown to include the sense of being "located at" or "directed at", especially in email addresses and social media like Facebook and Twitter.
Medieval monks abbreviated the Latin word ad (at, toward, by, about) next to a numeral. One reason for this abbreviation was that it saved space and ink. Since thousands of pages of Bible documents were copied onto expensive papyrus or hides, and the words at, toward, by and about repeated millions of times throughout the ages, a considerable amount of resources could be spared this way. 
In architectural drafting (hand drafting) many were taught to use this symbol as shorthand for "spacing":
  • 1/2" A.B. @ 32" o.c.
  • 11 Risers @ 7 1/2"
Somewhere along the timeline, after the transition to CAD, practitioners began to use the symbol where its meaning was not spacing but location; for example - Building Section @ Lobby.

In hand drafting there is some defense for this practice. It saved time and graphite - just like in medieval times!
But we are now in the 21st century!
It takes the same amount of time or less to type the letters "AT" than to hold the shift key while pressing "@". Certainly not more. Nothing is being saved.
Of these examples, which looks better? Which is easiest to read?
  • WINDOW SILL @ FIBER CEMENT SIDING
  • WINDOW SILL AT FIBER CEMENT SIDING
  • WINDOW SILL at FIBER CEMENT SIDING
  • Window Sill at Fiber Cement Siding**
One of the benefits of implementing Revit/BIM (getting rid of CAD) is that it provides an opportunity to re-think many of the practices that have been erroneously carried forward into this modern age. This is one.

**Stay tuned for my indictment of "ALL CAPS" text.


Thursday, September 27, 2012

Revit Work-Sharing File Protocol

Recently I attended a user group meeting that included a presentation on Revit Work Sharing and Worksets. Eventually three different users spoke about their procedures regarding central and local files, and all of them were different from mine.

Revit Worksharing was introduced in version 4 (2002?) and represented the first true multi-user BIM environment. With this innovation, all objects in the model were assigned to a collection; the "workset", which was required to be checked out by a single user. Conflicts still arose when an objects in different Worksets interacted with each other. These limitations eventually led to the development in version 6 (2004) of "element level borrowing", which lessened the need for Worksets, except on larger projects.

When Worksharing is activated, the single user file is automatically converted to a central file. Copies of the new central file are automatically designated as "local' files which must be periodically synchronized with the Central.

When this feature was initially implemented, all file management was manual. It was not unusual for inexperienced users to accidentally open the central file; one solution was to include the word 'central' in the file name, as a reminder.

Another common problem was the failure to save local changes back to the main file, locking other users out. This led to the so-called "best practice" of creating a new local file every day or even with each new work session. These protocols were originally all manual, and some users created external programs to automate the process.

Starting with version 2010 enhancements were added to make central and local file management more transparent. The Recent Files start-up window and the Recent Documents panel make it easy for users to select the correct file.



Now when users browse to a central file in Revit, the default result is automatic creation of a new local, in the location specified in Revit options dialog. The Revit user name is automatically appended to the central file name, which identifies it as a local file.

Some CAD users have developed the habit of browsing to a file and "double-clicking" it in Windows Explorer (which is fine for single user files). When users open a Revit central file by this method, or any other, they will soon receive a warning to save their work into a new local file.

As with CAD, when using Revit there is no reason maintain some strange attachment to procedures that have become obsolete. The Zen of Revit means developing a sense of "what Revit wants" and following it.




Sunday, September 16, 2012

“Core Only” Walls in Revit


Before the advent of CAD, on construction drawings walls were represented by two lines - which everyone understood to represent the wall’s entire thickness. The actual wall assembly was defined by details. The construction layers and finish materials of walls were always shown in larger scale views.

Then as now the standard for dimensions was to reference the face or edge or the core construction, because it must be placed first in the field.  General notes disclaimed “All dimensions are to face of structure unless noted otherwise”. When more specific direction was required, the letters ‘FOS’ or ‘FOW’ were placed next to the dimension line to denote the reference.

At one-eighth inch scale the size of a six inch wall is 1/16”, which is about as fine as can be drafted with pencil on vellum. In manual drafting, at smaller scales the same wall would be drawn thicker, by necessity. The level of detail was variable, depending on the scale of the drawing.

With CAD came the ability to add more detail and precision to drawings. Unfortunately, CAD did not have the human ability to automatically adapt drawing detail level to drawing scale, and management of this information by drawing layers (over hundreds of individual files) although possible, was eventually abandoned because it was impossible to maintain.

So it was all or nothing, and the practice of representing only the structural core of walls, and excluding finishes, evolved into the defacto standard for CAD.

The transition from manual production to CAD did not really resolve its problems; it simply exchanged old limitations for new ones. This compromise is one example of how the limitations of CAD were first accepted and are still perceived as obstacles to overcome in the transition from CAD to BIM.


Among the unintended side effects of this practice, with CAD room and building areas are often calculated by tracing a polyline around the perimeter of a space, not at its finish but at the wall core. Cabinetry and casework is often depicted as if the wall finish does not exist. These errors are not significant, but should hardly be defended when a better solution is presented.

Those familiar with its early history know that Revit was designed specifically to resolve the problems inherent in CAD. Revit allows dimensions to be referenced to structural elements, while also displaying the full thickness of the wall, finish to finish. Revit  also allows walls to be depicted with only two lines (coarse view) with unlimited options for color, fill pattern, and lines weight.

In Revit room areas are automatically calculated, with boundaries established at the user's preference. 

In addition, Revit area plans automatically apply rule-based algorithms for its calculations.


My advice to Revit users is to resist all temptation to use Revit to emulate the limitations found in CAD. Allow what is clearly obsolete to stay in the past where in belongs.