Parametric? That’s a foreign word to most people, especially ones that are not a part of the AEC community…and Parametric Family?…While on the surface this term seems scientific and complicated, having a greater understanding of what ‘this’ is, and what it can do to aid the designer towards the successful outcome of a project is very simple.
Of course all AutoCAD users are familiar with ‘blocks’. They’re great, most users have a ‘library’ of these blocks stored on their computers and have the ability to load these into a drawing when they need to insert a window, door, fixture, appliance, etc. The process of sorting through blocks to find the right size door, with the proper width, and height is a thing of the past. What happens when you can’t find that 3′ door width, and the 7′ height, with the 4″ head? In CAD, you would probably make a new block with these sizes, and before you know it, your small project already has 50 blocks loaded into it.
In Revit, you have the ability to build in multiple sizes of items into a single family. Whether it be a 24″ door, 30″ door or 36″ door, it is all one family. The drafter can choose these door sizes on the fly from a drop down menu, and interchange them with the click of a mouse.
So what is the advantage of using parametric families? At JL Architects, we have many national clients that use the same elements in their building designs. However, very few locations are exactly the same, thus custom sizing of elements is often required. For example, Zoe’s Kitchen typically has an outdoor patio with a railing that encloses the seating area. We have the ability to use a single family that has a ‘length parameter’ built in that allows us to adjust this railing from project to project to suit the sizes of a specific space.
As you can see from the illustration below, a Zoe’s Kitchen railing must maintain these proportions.
It does not necessarily matter whether this railing section is 12′ or 8′, our parametric family will ‘flex’ and adjust the spacing and lengths of railing members based on these fractional formulas inserted in the family parameters. This results in saved drafting time, which allows for increased efficiencies throughout the project.