Join Eric Wing for an in-depth discussion in this video Learning what a family is, part of Revit: Structural Families.
- Let's get started by explaining what a Revit Family actually is. For you AutoCAD users, it's a block that you insert into a drawing. Basically a group of objects that form a building component such as a desk or a window. Oh, but this is no ordinary block. In AutoCAD we had to insert a block, explode it, stretch it and put everything back on the correct layers. Not a family. Revit families are the cornerstone of BIM. When you insert a family into a model you get a fully parametric, data rich 3D object that can adapt to whatever is actually hosting the family.
For example, if I insert a window family into a wall, I don't have to tell the family what size the wall is, it just knows. Better yet, when I change the wall, the family automatically flexes within the wall. That being said, there are a few different types of families I would like to explore. The first thing I would like to look at are family categories. And the first type of family category we have is a system family. A system family is inherent to the model. To make a new system family, you have to select an existing family, duplicate it, then change the attributes to it.
System families include items such as walls, floors, roofs, footings, stairs, ramps and slabs. These families will be in your current model. You can bring them into another model by copying and pasting them. Another type of family are hosted families. Hosted families are actually created outside of the model and brought into it. Hosted families can include, framing, columns, door/window openings and trusses. Also we can look at angles and other miscellaneous metals that we see. In-place families occur when you need the surrounding geometry to dictate what your family is going to look like.
An in-place family is created just like a hosted family only you are doing in within the model. Unique plates and stiffeners, slab depressions, footing steps, wall bevels, items like that. Now we have family types. A family type essentially is when you have a family that you bring into a model, or it's adherent to the model, you have the family name. Now within that family name, you can have several types or variations of that actual family. For example we see our footing rectangular here.
We have all these different types 2-6" x 2-6" x 12" 3-0" x 3-0" x 12" Or you can duplicate a family and make your own to suit your needs. Families are parametric, but parametric does not just mean 3D. Parametric is adjustable. For example, if you look at the formulas in the screenshot here, you see we have all kinds of different formulas. This is a simple bolt. They are able to flex to any situation. They are parameter driven, they are definable. You can redefine a well-made family.
If the family was not made that well, it's a lot harder to define it. Throughout this course, we are going to look at making a well-defined family, and they are data rich. Building information modeling is what's in a family. You can put any information you want in a family. Again, it doesn't have to be 3D. Any family, 3D or not, can have as much parametric driven data as you want. Okay, so let's start making some families.
Following an overview of the basics, Eric provides specific instructions on modeling different types of families: foundation, framing, annotation, and truss families. He'll show how to perform 3D extrusions and build in flexibility with parameters, as well as create formulas, array parameters, and lookup tables.
- Understanding parameters and reference planes
- Creating extrusions and sweeps
- Cutting voids
- Building stepped-footing and other foundation families
- Creating columns
- Adding framing
- Working with metals
- Creating tags and annotations
- Printing sheets
- Creating trusses