September 2013 Newsletter

**** The 4specs Perspective

How Do Design Firms Use Bim Objects and CAD Details?

Several manufacturer's marketing people have thought that having a special spec section number for their products will guarantee them exclusive bidding. The same thinking applies to proprietary, lock-out specifications and CAD details and more recently proprietary BIM objects.

Many full-time specifiers use the 4specs discussion forum as a way to get answers to questions they encounter. The use of BIM Objects and CAD Details and the affect on product selection and specifications was recently an active discussion thread.

This discussion started several years ago and was recently reactivated. From my perspective here are some of the key statements. You can read the entire thread at the link above. [Note - several spelling mistakes were corrected for this extract]

March 2009
I am concerned that the indiscriminate use of manufacturers' BIM blocks embeds proprietary requirements in the database which has a way of making its way into the specifications. This may or may not be helpful depending on your point of view. I believe that CAD processes used to develop BIM models force earlier decision making on the part of designers which most people would view as a good thing. I believe, however, that the data being embedded in the BIM model may be less, rather than more, generic.

Moreover, I would suggest that the decision to use a particular product may be based on the availability of BIM blocks rather than a thoughtful evaluation of the produce in relation to the particular needs of the project and the value this particular product contributes to the project.

March 2009
I think Peter's concern is more firm-related than BIM related -- most of the firms I've worked with discourage the direct use of manufacturer's CAD and/or BIM blocks without having them edited for content. the idea of selecting products based on the availability of BIM blocks isn't any more professional than using products based on the manufacturer having a spec -- and then using it unedited.

March 2010
Ken has hit on the key issue with any spec preparation -- the communication between the team members and the experience and intuition of an experienced spec writer on the project.

Now that I have thirty years' experience, I can say (with no small amount of hubris) that I don't want less experienced people drafting the documents (or an "automatic" spec system) because in order for that to be useful, I have to be able to rely on the preliminary information. When I have a client provide the "50%" spec for me to take to final, it actually takes me longer, because I have to check the information that I'm given -- and verify that its useful and correct.

In my last job, the managing partner specifically did not want the specs tied to the drawings because the drawings (especially early on) contained too much erroneous information to be used as a template.

August 2013
I realize this is an old tread but it appears to be the best place for my issue. Our small office is beginning to do some projects in Revit and it is influencing the specs in a potentially uncomfortable way.

We do not link the plans and specs at this time but I am being asked to change or add some product types, models, etc. into the specs which is fine with me (part of the job).

However my concern/observation is that some of these changes/additions are being initiated because one manufacturer has a better BIM model than the products we typically specified. To date all of the instances where this has happened the new/additional products are comparable to the ones we always used. Still my concern is that product selection is being influenced by the CAD operator and not necessarily the best product for the specific application.

August 2013
you seriously import Revit models from manufacturers and make them part of your standard details? that's really the big issue here -- is importing information that your firm hasn't reviewed for best practices.

However, I assume that if your managing partner thinks that importing Revit models is a good idea that your concerns about products will fall on deaf ears.

Document your concern; specify the item shown with other suppliers who are comparable, and don't take it personally.

the offices I've worked for have been using Revit (or something else) for about 10 years -- not exclusively -- but regularly. NONE of our Revit models are copied from manufacturers, as are none of our specs.

August 2013
My concern is that products that we have specified and installed for years are now becoming the "or-equal" product because the Revit model was created (and our primary spec is written) around someone else who has a better Revit model. As an example: If Cookson or Cornell is my "go-to" for rolling counter doors but their Revit models are difficult to locate or are poor then some other manufacturer may be used. If they are reviewed and they do meet the requirements then that is fine but the "old standards" have been relegated to or-equal products not based upon performance, price-point, availability but rather the quality of their Revit Library.

August 2013
This has been a problem since manufacturer began distributing "standard details." As a summer intern I used to copy them (I still have the stone carving tools), later we CADded them, then we downloaded them from websites. Now, instead of 2-D details, we have "BIM Blocks." These were never as "neutral" as some of us thought they were, and we should have to recognize that they are a marketing effort.

There are several issues:

1) Wrong product for application. This may or may not happen as often as we think, but it can be the result of poor marketing information or poor understanding of the product on the part of the user.

2) Wrong information for project. What I worry about is embedding proprietary information into BIM files when generic information is more appropriate, but there are other issues as well. The most common example would be the use of a specific manufacturer's name or a trade name where a commodity product is required (think "Sheetrock" where you really want a note that says "gypsum board").

Once the "BIM block" is in the office library, getting it taken out is harder than killing a zombie vampire (or a vampire zombie). Even if one is successful in getting it deleted from the library, it usually has made its way into a couple of projects. At best, it gives the contractor and CA person a good chuckle; at worst, it can result in litigation. This is not a new phenomena.

BIM users, especially ones whose experience is focused on developing computer expertise rather than architectural expertise, often do not understand why these issues are important. An emphasis on productivity (getting more stuff into the file) leads them to take the easiest path rather than attempting to think the problem through to arrive at a more correct solution. After all, that is not really what they are paid to do. Experienced design professionals need to carefully review the output. When there is garbage in the output, the source garbage in needs to be found and deleted (easier said than done).

Let me know if you have any questions or comments. Suggestions and comments are always appreciated.



Colin Gilboy
Publisher - 4specs
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