Revit Standards of creation

In response to my last blog (FAR Quality Control – 6/18/09) I received several comments about NIBS and Style Guides from one of the LinkedIn groups. I agree that Style Guides are necessary guide lines with starting points showing how software should be used, however, that was not what I was trying to convey. Maybe NIBS will address the issues I am talking about - however, it has been my experience when you wait for a committee to do something or address an issue, we may be waiting a long time.


I looked at the date of the Style Guide from Autodesk and started wondering why they did this after loading all of the data (families) into their system. I feel this should have been implemented from the start, prior to loading the data. There is a saying about databases "Garbage in - Garbage out". Once you have the garbage in there, repairing or fixing it can be an impossible task. Being a software company, Autodesk should have known better. Autodesk’s role with the standards should stop here and let the industries decide those items. Maybe Autodesk, along with the other software companies should be members of NIBS and have the same input as every other member of NIBS.

Enough stated about Style Guides. What I really would like to address are the Standards of Creation - having the right data and the naming of that data.

The following is a simple example supporting what I mean regarding the need for Standards of Creation. If you start with a window in Revit you will find predefined items such as built-in Parameters, etc. The big question is ‘How do we define more specific items?’ For instance, with a double hung window you have lower glass and upper glass, do we show double or triple pane? And, if you do, how do you name these items? Also shouldn’t there be a glass size variable in a window so at the FM level they would be able to get the glass cut if they needed to replace it?

I think everyone agrees we need to have consistency for this type of data across the industries and having consistent data across different manufacturers would be a tremendous improvement for everyone involved. Imagine if window manufacturer A and window manufacturer B (as well as all of the generic window manufacturers) were following the same Standards of Creation.


Developing new Standards of Creation is a huge undertaking. We feel CAD Enhancement’s FAR process will be able to begin addressing this concern and will be adding it to our testing procedure. We will be watching NIBS and even consider becoming a member so when more detail Standards of Creation are released we will be able to work with them. CAD Enhancement’s FAR process will be able to incorporate the standard changes with extreme efficiency while utilizing the ability to communicate with both the manufacturers and architects who are using FAR and if necessary, will be able to update their families on their system and in their projects.

Patrick K. Johnson

Developing Good Modeling Technique

We are seeing more modeling coming from those within the Architectural Industry using Revit so I thought I would talk about some basic concepts to help develop good modeling technique. In the past I have seen the results of poor modeling technique coming from the Manufacturing Industry using Inventor, Solid Works, etc.... The basic concepts I’m referring to can be applied to both industries as a means to develop good modeling technique.

What I am talking about is applying constraints as you make your model and the use and applying the two different types of constraints; one being dimensional constraints and the other geometric constraints.

• Dimensional constraints are exactly what it says they are dimensions that you apply to your model. These dimensions can be just a number or a parameter or equations.
  
• Geometric constraints are the constraints such as collinear, align, etc... These constraints will tie your sketch together without the need for dimensions.
  

When creating your model the first technique you need to do is to tie your model together with geometric constraints - I cannot tell you how many models I’ve seen in the past with dimensions at a 0 value. What I have tried and found to be extremely helpful is to use dimensions that are required on the drawing - Believe it or not 99 percent of the time these are only the dimensions you will need to put on your model. I also want to point out that using geometric constraints also creates a clean model which makes it that much easier to update in the future.

Another important concept to keep in mind is to make sure that your models are fully constrained - which results in predictability when making changes to your model. Just imagine putting your model in a project file and when you try to change a parameter, the results show only half of the updates you thought it should have. That is always the result of a model not being fully constrained.

The final basic concept you should keep in mind when creating your models is to test, test and test again. Do not be afraid to test while you are creating your model and again, after you have completed your model.

Managing Revit Families

Another problem that manufacturers will experience by having the Revit families for their products available on various websites is the management of their product data. What I mean here is that when manufacturers provide their product data and Revit families to the world on websites, other than their own company websites, they increase the chances of losing control and credibility for their product(s).

Losing control:
As manufacturers allow their product data to be made available on the websites providing libraries of Revit Families and the end users start storing that data on their servers, how can you manage any product upgrades and changes to make sure those changes are captured on the end users project files?

First: I really believe that manufacturers control their data by having the end users come to their own company website and have the family dropped into the project file thus eliminating the need for the end user to store the Revit family. If the end user decides to store it in their servers - they need to know of the possibility that the product can change.

Second: I also believe that one parameter which should be added to a Revit family is a ‘revision/version of the product’ that is being used. This would be a good way to make sure the building product manufacturer knows what is out there as well as for the end users to feel confident that the Revit family they are using is what they desired and has not changed, as it would be confirmed it is the most recent revision/version of the Revit family created.

Third: Another feature that should be added to a manufacturer’s own company website providing their product data in Revit families is the capability to allow the end user to request the amount of detail for a Revit family. Each project and/or end user may have different requirements for the amount of detail needed per family. At this time I have not seen any websites offering this option.

These are just a few comments regarding the management of Revit families. In the near future I will adding more detailed commentary.
Feel free to comment and give us your ideas and concerns with Revit families on the Web.

Thanks.

Patrick Johnson

Revit Families found on the Web

I am hoping to get some comments on this subject to see if I am off/on base on my thoughts of the Revit Families on the web. Can you trust the Revit families that are found on the web to be accurate and usable in your project file.

There are many web sites out there that either sell families or allow you to earn points to upload and use to down load. Autodesk has gotten into the mix with Autodesk seek, which appears that quite a bit of their data have come from other web sites and users and as far as I can see these are in their database "as is"

The one issue I have is the lack of quality control that appears to be consistent with these web sites on their data. This makes me very leery on using this data - you know the saying when it comes to databases "Garbage in - Garbage out". Any in-accuracies will always be caught at the most in opportune times such at the construction site.

If you are looking to download Revit families on building product manufacturer data, you may be better off to go to the manufacturer's web site or contact the manufacturer to obtain families. At least you have to assume that these would be accurate in manufacturer data.

If you do use these sites, I highly recommend that you set up a process and quality control mechanism to make sure these families are accurate in their data and meet your standards prior to allowing them to be inserted into your project file.

Let me know your thoughts on this issue.

Patrick Johnson
President
Cad Enhancement, Inc