Welcome to Part 11 of this 17 part series on creating your own custom model components using the Family Editor. If you have just stumbled across this article without reading the previous parts of the series, you may want to start here. In part 6 “Parameter Power” we introduced the concept of parameters and how they allow you to add dynamic flexibility to your components. In this article we will take a much closer look at parameters.

We’ll look at various parameter type and what you may use each type for. A step-by-step example will help put theory into practise. You may have heard of the concept of “Shared Parameters” and “Family Parameters” before. In this article we are going to deal strictly with Family Parameters only. The use of Shared Parameters is a very powerful tool and warrants it’s own distinct article.

OK, so onto parameters! As we’ve said many times before Parameters are at the very heart of Revit. It’s one of the key differences that separates a “BIM (Building Information Modelling) System” apart from the so called “Dumb CAD systems”. For the majority of the time, your “parameter of choice” will be a “length” parameter. For example, you wish to control the length of a wall, the width of a door opening, the height of a ceiling. All of these need a “Length” to define them. But what other Parameter types are there?

Let’s take a look at each one in turn and discuss when and how they may be used. The list of available parameter types are as follows…

So let’s start off with an nice and easy one!

A Text parameter is REALLY useful for adding notes, comments, reference numbers, etc to your components. When you get used to creating your own family components and adding parameters, you’ll find a myriad of uses for the Text parameter.

Very similar to the Number parameter, Integers (as the name suggests) can only hold values that are whole numbers.

The number parameter is useful when you want to store any numerical value in your component. You will probably be using these parameters along with equations to generate automatically calculated values.

The Length type parameter is one of the more commonly used ones. You will use this when you want to be able to change one of more dimensions in your component.. 

The Area type parameter is useful as a calculated value, when you are interested in a surface / floor area.

Very similar to the Area type parameter but obviously with the inclusion of a third dimension.

The Angle type parameter is useful when you need to be able to include the ability to specify an angle within your component. For example- the angle of a rafter from the horizontal.

Ah, the old URL parameter type. I LOVE this one! This gives you the ability to store an URL (fancy name for a website address) within your component. Personally I think this is a really powerful parameter. If you then include this parameter in a schedule of your components- you can then click on any of the associated URL’s and be taken straight to that website. This also works if you PDF the schedules- as long as you view them in one of the latest PDF Viewers.

The Material type of parameter allows you to define materials within your component. This is useful if you need to be able to give the user (of your components) the ability to change the material without having to edit the component using the Family Editor.

And finally the “Yes / No” type parameter. You will probably be able to think of millions of uses for this one! The is only one rule to remember- it can only accept one of two values- either “yes” or “no”! Is this a Fire Door- yes or no? Is this item included within the contract- yes or no? You get the idea.

In the second half of this article we will look at how you actually include these parameters in your own custom components.

Continue to Part 2 of this Article