Thursday, October 27, 2005

Revit Family Editor

Here in lies the key to completing successful projects using Autodesk’s Revit. Without the ability to create or edit your own families, the whole Revit migration cause is lost. After purchasing the software, you generally get fixed into a training course, with hopefully a reputable Autodesk Accredited Training Centre, who teaches fundamentals for 5 days. There after you are left to your own devices on mastering Revit. Revit families can and will “eat you up and spit you out”

Without mastering the “Family Editor” which generally doesn’t feature during “Fundamentals”, you will be even more lost. Every Project is unique, therefore, the need to create unique content to complete successful CD’s is even greater. It’s the complexity to which you create and manage these families, that makes the whole experience unique in it’s own. Prior to R 8.0 the Autodesk Revit Family Editor was very detached from the program. With the new added “Edit Family” Button on the “Options Bar” editing families is now made so much easier

The whole concept behind families is that of building a library, much like blocks. But instead of 3-4 different baths, at different lengths, we can now create 1 bath to suite all. I like to think of it as “one size fits all”…….Parametric. Although Revit does allow you to create families with in the project namely “in Place Families”, I strongly advise against it. Purely, for the reason of, RE-USE. Create the family once and RE_USE over and over. Create with in the project and it becomes project specific, with no way of saving out as yet!

We are currently experiencing the benefits to our extensive library which we started building in 2002, and are still adding to it. It is now a case of just populating the database with components and printing schedules. All the information is stored with in the family needed to complete the relevant schedules of data.

I have recently covered the standard UI for Revit. Now we tackle the “Family Editor” UI.
Upon creating a new Family, Revit first of all asks to which supplied template would you like to categorize the new family. These templates are all individually laid out with all the necessary start up kits pertaining to that specific model/category. Choosing the correct family template is crucial to the start of a new life. Having said that, don’t be concerned though if you have created the family under the incorrect category, it can be changed and this will be covered at a later stage.

You will notice first of all that the “Design Bar” looses all it’s tools and is replaced by the “Family Editor Design Bar”. In it you will find all the necessary tools to create your new Family. The tools available differ from template to template.

The biggest issue we had to deal with, after converting to Revit, is of course, all the cad symbols, “blocks” we had collected over the last 12 years of Autocad – “Legacy Data”. Especially, the symbols provided by manufactures that we used to filling our drawings with. We place the block that actually represents the plan representation of the fixture we intend to specify (this also defines a unique look to our drawings). For example, we have over 30 basins/vanity’s to depict the correct specification. So to keep with-in our office standards, we had to transfer all this legacy data. (fortunately we had students that I trained up to do this for us). In the Following exercise we will be covering exactly that.

How to, “REVITIZE” your current library from "Legacy Data".

Alternatively you pay money for a Revit implementation specialist to come and help.

Wednesday, October 26, 2005

Revit Formulae

So... I will just jump straight in here.
Many of the formulae conditions can be replicated re-used etc.
The Help files are most useful when starting out with formulae in Revit.
Also hunt around in

Here is some "help file" extrapulation....

You can enter formulas for calculating parameter values. Formulas may include numerical constants and other parameter names. For example, the family could have two parameters named Length and Width. The value for Width might be calculated with the formula Length/2.

Formulas are case sensitive. If the parameter names have initial capitals, you must enter them in the formula with capitals. For example, the parameter name is Width. You type width * 2 in the formula. This is ambiguous to Revit Building, and it does not accept the formula.

Formulas support the following arithmetic operations: addition, subtraction, multiplication, division, exponentiation, logarithms, and square roots. Formulas also support the following trigonometric functions: sine, cosine, tangent, arcsine, arccosine, and arctangent.

For numerical values in formulas, you can enter integers, decimals, or fractional values.

Formulas are available for instance parameter values in the project. You must begin the formula with an equal sign. For example, as you sketch a wall, you can enter a formula for the temporary dimension for the wall. Click , and you can enter formulas for numerical properties of the wall, such as Unconnected Height and Base Offset.

TIP: Keep your units consistent. Do not mix units in your formulas. You can use constants with no units assigned to them.

Length = Height + Width + sqrt(Height*Width)
Length = Wall 1 (11000mm)+ Wall 2 (15000mm)
Area = Length (500mm) * Width (300mm)
Volume = Length (500mm) * Width (300mm) * Height (800 mm)
Width = 100m * cos(angle)
x = 2*abs(a) + abs(b/2)
Create the family geometry.
Create and label dimensions to the geometry. See Labeling Dimensions. Do not select the Instance Parameter option. In the Family Editor, formulas are available for type parameters only.
Click Family Types from the Design Bar.
In the Formula column next to the appropriate parameter, type the formula for the parameter. Notice that the formula begins with an equal sign (=).

Formulas can comprise conditional statements. You enter conditional statements in the Formula box for a numerical parameter.

A conditional statement uses this structure:

IF (, , )

This means that values are entered for the parameter, depending on whether the condition is satisfied (true) or not satisfied (false). If the condition is true, return the true value. If the condition is false, return the false value.

Conditions can use numeric values, numeric parameter names, or Yes/No parameters. You can use the following comparisons in a condition: <, >, =. You can also use Boolean operators with a conditional statement: AND, OR, NOT. Currently, <= and >= are not implemented. To express such a comparison, you can use a logical NOT. For example, a<=b can be entered as NOT(a>b).

The following are some sample formulas that use conditional statements.

Simple IF: =IF (Length < 3000mm, 200mm, 300mm)

IF with logical AND: =IF ( AND (x = 1 , y = 2), 8 , 3 )

IF with logical OR: =IF ( OR ( A = 1 , B = 3 ) , 8 , 3 )

IF with Yes/No condition: =IF (Long, 50, 60) where Long is a Yes/No parameter defined as Long = Length > 40

Embedded IF statements: =IF ( Length < 35' , 2' 6" , IF ( Length < 45' , 3' , IF ( Length < 55' , 5' , 8' ) ) )

The following are valid formula abbreviations.

Addition— +
Subtraction— -
Exponentiation—^: x^y, x raised to the power of y
Square root—sqrt: sqrt(16)
e raised to an x power—exp
Absolute Value—abs

Tuesday, October 25, 2005


My good friend and Reviteer has joined me in contributing to this site.
Welcome Mike!!

Friday, October 21, 2005

Getting to know Autodesk Revit's User Interface

The following image outlines the basic user interface for Autodesk Revit.

Know your "Options Bar".
Autodesk Revit’s User Interface is by far the easiest I’ve come across in terms of Architectural software.
Behind the Standard UI is in fact a “Hidden UI”. It exists in the “Options Tool Bar”
The biggest piece of advice I could give with regards to the User Interface is, constantly monitor the “Options Bar”. With almost every command the “Options Bar” changes it’s state. Get to Know it!!

Know your "Properties".

Together with the “Options Bar”, the “Properties” dialogue box, is by far the most complicated parts of the UI.

There are two parts to the dialogue box. Namely :
1. Instance parameters: Parameters that effect only the selected object and no other.(found in the first part of the diag.)
2. Type Parameters: Parameters which change every object in the project. (second Part of the Diag.)
With every element you select the properties and parameters are different. There are many standard Parameters that Revit automatically assigns, especially in System Families*. Since Revit 7.0 the “Properties Dialogue” took on a much needed overhaul. Parameters are now categorized, and easdier to find. Still, when it comes to custom families anyone can put anything anywhere. So, Get to know what to look for!

Due to the fact Revit is a Parametric Modeler, you more often than not change the parameter to change the object/model. There's no "Stretch" command. However since release 8.0. Instance length parameters now have "handles" grips, that one can use to pull or push to change a size.
Get to know your parameters.

*System Families= Walls , Floors, Roofs, Ramps, Stairs, Railings, Ceilings.

Wednesday, October 12, 2005


Before we get started on the “Best Practices for the Family Editor” you will probably wonder, as to what makes us qualified to give instruction.

Together with an Autodesk Reseller, I started researching Revit from Revit 4.0.
Autodesk then added Revit to their “stable”.
Approximately 8 months later, we then selected a few reputable architectural firms, to run pilot sites of Revit 5.0. Only three took the bait, out of the selected ten. I then took on the task of training the select few. Afterwards, helping them in implementing Revit in their offices, with the sole intention, of not letting them touch, any cad software other than Revit for the next three months.

Over the next two years Revit took off, exceeding all expectations. I trained an excess of 120 individuals, as well as, sat through their pain in trying to implement.In that time we also took on the task of building all the local standards, as well as local manufacturer’s components, as families. Together we built a library of over 1.2GB. This gets sold as part of a Revit package, by the reseller.

Accomplishments continued....

Over the next year I continued to implement Revit at A3 Architects-Inc, who happened to be my first pilot site in South Africa. Combined, we have rolled out at least 8 projects, done only using Revit.
Three of which are large Hospitals, the largest, a 27 000sqm 200mb complete database file.
The smallest hospital of the three, benefited largely, on all the families we had already set up, and standardized. Thereby, making it the quickest set of “Construction Documentation” rolled out in this office. All three are currently under way with construction.

We took time in establishing an office standard that the three of us (the Office Family Creators) would stick to. Constantly having “Family Planning” meetings (I sound like a psychologist), which would determine the best methods needed, to make the next set of families benefit us the most, in terms of the look and the data attached.

However, not always did we take the best or most efficient path, and would have to “Reverse Engineer”. But the outcome of all our research is what should benefit you, in creating a successful and complete Family and Library

Monday, October 10, 2005

New To Blogging

I have found Blogs! I find this concept quite fascinating, and thought,I too would start something in which I can share the knowledge.

I am a Revit Implementation Specialist in South Africa. I started on Revit even prior to Autodesk’s buy out. Revit 4.0.
I specialize in Large projects and the efficiency in running them using Revit. Through my experience I have become somewhat the Family Specialist, for here-in lies the secret to successful projects in Revit.

After helping various users on AUGI to sort there families out, someone posted "Why dont you write a book".
Thru' this Blog I will attempt to share our findings in family creation inside Revit. Starting where we started, with the simple stuff thru' to the advanced families we are busy creating today.

After purchasing Revit from a reseller you probably attended a course of some sorts, and then you are left to your own device to try take on the daunting task of a complete project using only Revit to complete your CD's.

Well I hope to shead some light on this very powerfull tool that lies within Revit. The Family Editor.