"Family Type" Parameter in a Type Catalog Part 2

JING is great, but the .swf files are a pain to embed on Blogger.

Who's afraid of the Big Bad BIM? finally has a YouTube Channel. Hooray for technology.
The quality still isn't great. From Jing (freeware) through a trial .swf convereter (also free) to YouTube. I guess I will have to spring for Camtasia after all... Fathers day is coming... Hmmmmmmm.

I recommend viewing AT YouTube's site>Clicking the HD button for higher quality>and watching in full screen.

"Family Type" Parameter in a Type Catalog

They say that absence makes the heart grow fonder. Let's hope so fans. Of course I think the actual quote is "Absence makes the heart grow fonder... for someone closer." If that's the case, I hope my favorite Revit bloggers got a bump in readership. :)

In a comment on an earlier post, a reader asked if it is possible to drive Nested Families with a type catalog. In a subsequent email he issued a friendly challenge to prove that it can be done and show if a Yes/No parameter can also be controlled as well.

Nothing will get me blogging faster than a challenge. Thanks Matthijs.

What follows are links to a couple of quick video clips that I hope explain how it can be done.

Showing the Parameter Types

Loading and Placing the Family

(bonus: note that you can drive "instance" parameters with a Type Catalog)

Here is the Type Catalog. I always like to create and edit my type catalogs in Excel and then save to .csv format and change the extension to .txt. It's just easier for me.

As you can see in the second clip, I alternated each parameter value. Just make sure that you spell the "Family Type" parameter the way it appears in the value cell in the Family editor.

Oh, and the 0's and 1's? Binary, Baby! 0=No 1=Yes.

Good luck, and keep the challenges coming.

Revit MEP (Plumbing) Piping Flow: another second class citizen

Warning: What follows is a rant fest filled with WAY more information about MY ideas of how both plumbing design and Revit MEP work. Any deviation from reality on either subject can wholly be attributed to a 14 month old daughter, a pregnant wife and a looming Revit configuration deadline. Please excuse my definite lack of plumbing design knowledge. See one, do one, teach one, I always say.

Revit MEP is ALL about propagating information throughout the model.

Spaces can be assigned a required Air Flow value.
Air Terminals know what space they are in.
Spaces know how much Air Flow is coming from the Air Terminals it contains.
Duct connected to an air terminal knows how much air is flowing through it (based on what the terminal is providing to the room.)
Variable Speed Fans (VSF) know the SUM of the flow from all the terminals connected to it downstream (Revit is doing the math on the fly.)
And so on and so forth all the way back to the Roof Top Unit (RTU) that SUMS all the VSF (and therefore all the terminals) that are connected to it.

We can tag and schedule this information fairly easily. And, it's used in sizing calculations.

Sounds keen.

Enter Plumbing pipe systems. (Cue ominous musical score.)

On the surface they work similarly to HVAC duct systems. But any plumbing designer will tell you (you have to listen closely they probably won't repeat it) that flow through a plumbing systems is different than duct systems. It's even different than flow through hydronic, or process systems.

The difference is DIVERSITY. No we're not talking about multiculturalism. Simply put, a system that contains 1 watercloset (WC) (that's toilet to the rest of us) has a 100% chance that all WC will be flushed at exactly the same time. Therefore the system is designed to accommodate the flow of that WC. A system with 100 WC has about a 0% chance that ALL will be flushed at the same time (aside from High School pranks.) Plumbing designers use a diversity factor along with Fixture Units (FU) to determine the most likely (design) flow in their systems. FU are assigned to fixtures (WC, sinks, etc) by Authorities Having Jurisdiction (AHJ(why is it always a TLA(Three Letter Acronym?))) so they can vary by locale. In short the designer totals the FU on a system and applies the diversity factor (which they get from a table) for the number of actual fixtures and that tells them the flow they need and therefore the pipe size. Whew! (Did I really have a 3rd level parenthetical statement back at AHJ?)

Why does all this matter? Well, for one, Revit doesn't get to look at that diversity factor table when it's computing flow. I can't even imagine the math used to derive flow from FU without it. All in all Revit does a darn good job of computing that flow and reporting it out to us. Connect a bunch of sinks to a pipe that connects to a water heater and the pipes will total the FU (and the resultant flow) from however many it is actually connected to.

Now the rub. The pipe that connects to the equipment (water heater) reports it's FU and flow fine, but NEITHER THE FU OR THE FLOW propagates to the equipment. You can create family or shared parameters based on both FU and flow. However, when mapped to the same parameters on the family's connectors (similar to how you cause Air Flow to propagate through VSF) you receive NO report. And, it will not propagate upstream.

At least I can't get it to work (and I tried every combination of connector settings related to those two parameters.) After talking with an Autodesk rep, it came to my attention that Revit MEP wasn't designed to pass flow through equipment in plumbing systems (where flow is calculated from FU.) So that means, I can't schedule equipment (like water heaters or softeners) and have the schedule show the actual flow demand on the unit (based on the system it is connected to.)

A bug? Unforeseen functionality need? I think it's just that the Revit code jockeys took it the wrong way when they were told to work on the FU systems...

BTW, this has been logged as a functionality request to the development team. Here's to making plumbing flow as useful as it's first class cousins Air Flow and (hydronic) piping flow. :)

Trouble finding hidden elements in Revit? Use; Select by ID

This handy feature can really save you when you are trying to figure out what objects are causing issues in your project.

The other day I was trying to resolve some warnings related to switching a wall from one type to another that was not as wide in section. I wish that I had taken a screen shot of the warnings... there were 18 warnings (cannot be ignored) and 9 errors (Revit telling you that you should pay attention and see if what you just did was really what you meant to do.)

The project was fairly far along (actually CDs have been issued, but there is some clean up going on in the model.) Swapping walls at this stage can cause all sorts of issues.

In this case all of the warnings and errors were related to a ceiling. I created a new section and oriented a duplicated 3D view to it so that it encompassed the wall in question. I selected the ceiling in the warning tree and clicked the "Show" button but it wouldn't highlight in the view.

So, I wrote down the ID number (you can't copy/paste here, so you have to go old school.)

(I guess you could screen capture like I just did to get this image though.)

Now, go to "Tools" Drop-down menu>Element IDs>Select by ID

Enter the # into the dialog and now you can either use the "Show" button to highlight the element, or the "Select" button to grab the item and modify or delete it.

If you are trying to scout something that is deeply hidden in the model:

Duplicate the Default 3D view

Use the Select by ID feature

Use the "Isolate Element" command (click the eyeglasses) to hide everything else in the project.

Now you can activate the Scope Box for this view and crop out most of the model to get a better idea of where the elemnt is and what may be causing your issue.

Good Luck and Good Hunting.

The Key to Giving 100%

I don't really like to link to others Blogs. But you just can't argue with logic.

Autodesk 2010 Design and Engineering Software Product Line Now Available

YAY!!!

I hope you're on subscription and your copy is in the mail...

Follow the link to the full press release.

Revit Type Catalog Tip

Type Catalogs are a great tool to drive parameters and to keep your project file size under control.

Some families (like structural wide-flange steel) have so many types that it is nice to only bring the types that you need into your project.



To create a Type Catalog, start a new session of Notepad or some other text editor (not Word though, the formatting will cause errors in the Catalog.)

The first line lays out all the parameters you want to control. In this example I only used one parameter, "Type Comments." I like this parameter alot. It's in every family and isn't used by anything else. By default it is blank (more on that in a minute,) but you can use it to tag custom ID information for that object.


The second line begins with the Type Name, then a comma (this is a comma separated value file.) Followed by the values for the parameters you are controlling, again separated by commas. We'll keep it simple here. I do want to mention though that when working with complex Type Catalogs, I like to import them in to Excel. That way they are separated by columns, instead of commas. Just save it out as a .csv, then change the extension to .txt and it will work fine.

The purpose of this post is NOT to go into too much depth about Type Catalogs. There are decent instructions on the basics of Type Catalogs in the Revit Help file and a slightly more in depth treatment in the Autodesk Family creation tutorials.

Name and save this file in the same folder as the family.

When you go to load the family, you get the dialog below. Control or Shift Click to select the types you want to load.

Click OK and you get...

This warning... Hmmmmmmm,

It actually does exist. It's just blank in the family. Since there is no data for the Type Catalog to override, Revit disregards that column of the catalog.

So, open the family. Place a default value in the parameter. It doesn't matter what it is, it will be overwritten by the catalog. Save it. And reload it into the project.

To show what we have, I created a quick tag that reads the Type Comments from the family.

To take on e step forward, create a new type in Family editor and load it into the project without saving or editing the Type Catalog. What value will the Tag show? The default...

In short, if you ever get the "Parameter doesn't exist in the Family" warning, check the family and make sure there is some sort of data in the field. It should work fine after that.

BIMwash, the new snake oil?

I'd like to take a moment and try and define a new term.

BIMwash.

A portmanteau (a word that contains two words and combines their meanings) of BIM (building information modeling) and whitewash ( a thin paint-like coating that washes away slowly in the rain.)



More and more projects are requiring BIM. Sometimes the Design firm is requiring BIM from the GC and subs. Sometimes the Owner is requiring that everyone use Building Information Modeling. This is GREAT! I mean this is what we have been preaching and railing about.

Here's the rub though. BIM has become a BUZZWORD. Not to the extent that "Green" has, but a buzzword still. Now that everyone's talking about this thing called BIM, folks are starting to sit up and take notice. Heck man, there's money to be made here. We can do this BIM thing. We already model in 3D (sorta.) This (insert any BIM authoring software) looks pretty similar. We can't get left behind on this. RFPs (requests for proposals) are coming in asking for BIM. Let's go!

So XYZ Design (or Engineering, Builders, etc etc.) gets a couple seats of software, spend some time learning how to use it, and get it set up so they can plot documents to their standards. Yahoooo, we're on the BIM-train. Let everyone know, WE DO BIM!

Whoa, hold the phone, Buster. What do you mean you "Do BIM?"

Ummm, we use "Brand A" Software and... produce a BIM.

What's your deliverable?

Duh, the industry standard 2D CD's. You can't get away from that. Oh, and we can show you exactly what your building looks like with renderings and walk-throughs.

So, since Contractors, Subs, Design firms, even Owners all have their own ideas of what is BIM, are they wrong?

Yeah, I think they are.

I'm not going to rant and rave about what is and isn't BIM. Just Google it, there is plenty of discussion. What I will say is, there are plenty of firms out there that have jumped "on board" and are "Doing the BIM."

Educate yourselves. Have a serious discussion at your firm. What is BIM to you?

Everyone wants to get something different out of this. The Designer wants to validate design and communicate design intent in a new and easy to understand way. The Contractor wants to query the model and take off accurate Quantity of Materials and investigate "Buildability," dealing with interferences early in the process. And the Owner wants a BIM that they can use throughout the lifecycle of the building. Let the world know what you do or exactly what you want. Define it internally before you put it out before the public.

If you are about to issue a RFP that requires BIM, do yourself a favor and SPELL IT OUT. Define exactly what you are looking for. That way you have a better chance of getting what you want. And please, if all you want is rendering and walkthroughs, say that. Don't even use the term BIM.

If you are a Design, Engineering, or Construction firm, know what your strong points are. Know what you can and cannot deliver. Don't oversell your abilities. It will only come back to bite you.

And if you're just using the term because "everyone is doing it," STOP.

Don't be a BIMwasher... it's all likely to wash away in the rain...

Open Source Building Information Model (BIM) Server (Round 2)

David Harrison linked to a post on his site that gives a far more in-depth discription of what a BIM Server is and how it could effect the industry. It can be found here.

I figured I would bring this to the front page.

Thanks Dave.

Open Source Building Information Model (BIM) Server

An interesting idea. I have to admit I found the site a little lacking in useful information. But then again, I have to plead complete ingnorance when it comes to servers.

Check it out here.