Starting a Revit Family
Many organizations have made the choice to switch from 2D drafting (e.g., AutoCAD®) to 3D modeling (Autodesk® Revit®) over the last 10 years or so, but there are still some out there who haven’t yet jumped ship.
Let’s not forget those who are coming into our industry and are just starting out and need to come to grips with things for the first time, just like when people started with drawing boards many years ago. They needed to understand drawing using pens and pencils at scale in the drawing offices.
If you are one of those people just starting out with Revit, you may feel there is a fair amount to learn, and I won't lie—there is.
It is interesting that on many projects I have been involved in over the last 13 years or so I would still produce 2D drawings for the construction teams to build on site. This is still the case today.
When I switched to using Revit Structure, we were not even being asked for Building Information Modeling (BIM) or for 3D as part of the delivery. When we started out, none of the architectural or building services practices we worked with had even moved into using any 3D modeling software solutions. So even though we were using Revit to build models, we still issued drawings in DWG and PDF formats.
A major part of using Revit is the families we all use to create the components within the models to meet the specific needs of each project built.
Families are the main building blocks in Revit. A family is a group of elements with a common set of properties, called parameters, and a related graphical representation. They can be structural elements such as columns and beams, foundations, reinforcement, or nonstructural such as doors, windows, luminaires, or even annotation elements such as tags, dimensions, drawing frames, and so on.
On installation of Revit you get a basic standard library to use, which should be good enough to start modeling simple structures. Once you start building more complex structures, you’re likely to require further families creation.
Revit Family Types
There are three types of families used within Revit: system families, loadable families, and in-place families.
System families are embedded within a project template or project file, so they are not loaded into a model, but can transferred from one file to another. They are the basic building elements such as walls, wall foundations, floors and roofs, drawing frames, gridlines, levels, dimensions, etc. So when creating new types, you are required to take a copy of an existing family and modify its parameters.
It is recommended that as you create new types during a project, you transfer them over to your company template file. Then you will have a library of types to choose from once you start a new project. Alternatively, you could have a basic library in your template with system families that are used most often, then have another template/project file which holds your company’s complete library of system families.
Loadable families are created independently of the model and loaded into the model as required. They are created using their own template file (RFA), are customizable and allow the creators to set up a library of types. These can also be called component families. They are separate from the template file and can be loaded into a project, which helps reduce the size of your company template file.
These are bespoke elements that you may create directly within a project, not outside like loadable families. In-place families allow you to create families similar to loadable families, but also allow the creation of free form or custom shapes not possible to create as a system family, such as walls, floors, or roofs. Note that these cannot be exported to other projects.
Before you create an in-place family in your project consider that it may be better to create a system or loadable family as you may need to use it again outside of your current project.
Figure 1: Family types
Each family is part of a category, which is a classification for families (e.g., structural columns, structural framing, etc.). Families are grouped and sorted by category in the template/project file found within the project browser.
A family type can have any number of variations for users to choose from (e.g., different column sizes).
As part of a family they have Instance and Type properties. The instance properties contain information or settings applied to that individual element, such as column constraints top and bottom. If this is changed, it will affect only that instance of the family.
Under the type properties there are the parameters set for that family type. (e.g., steel column default dimensions, structural section geometry, etc.) This will be the same across the whole project for that type, no matter how many times it is placed. If any changes are made to the type parameters, the change will affect all families of that type within the project.
Hosted or Stand-Alone
Families can be host based, which means they are dependent on another element to host them such as a wall, floor, ceiling, roof, or even a face of another object.
Stand-alone families are elements such as a column or maybe a piece of furniture that do not need to be hosted to another element.
When creating your own families, before you even start you really need to plan it out first. For example, if you’re creating a new foundation, ask yourself: is it going to be a system, in-place, or loadable family? Well, it is not going to be a system family and an in-place family doesn’t seem to be the most logical. Therefore, a loadable family is the best option. It can be used across all projects—you can make one or a parametric family with multiple sizes included.
I have set up a family creation procedure, which I ask any members of my team to follow when creating any family. A few questions can be included at the start to help planning the type of family it needs to be.
Figure 2: Family element
Family Creation (Templates)
It can be so easy to just select any family template, but you really need to consider what you’re actually creating. If it is a grid head, there is a family called Metric Grid Head.rft. if it is a foundation, Metric Structural Foundation.rft. These will give you the basic settings you should need for those types of families. Bear in mind that there are some generic family templates that help if it is a face, floor, or wall-based family, for example. You can use one of the default families and edit it, but be careful as you are editing a family you did not create.
Tip: When you start creating families and find you’re adding the same standard parameters or information to all families of the same type, why not create a new standard template with those included to save time later?
Family Creation (Family Editor)
If you are creating or modifying a loadable family, the Family Editor is the place to do it in Revit.
Tip: I recommend opening an existing family first and have a look around to see how the family has been created.
When building a family, don’t complicate things by adding loads of complex geometry or constraints, which may not be required. If it isn’t needed, then why add it? You can always come back later and include it if required.
You will need to include some parameters to help constrain the geometry and add technical data for the family. Make sure you choose the right parameter types. Family parameters are created in the family editor, but don't appear in schedules or tags. Shared parameters are created in an external text file and can be placed into multiple families or projects. These appear in schedules or tags.
Tip: Make sure you test the family as you create it. You don't want to get to the end and find it doesn’t work. Then you will find yourself spending more time trying to find the problem.
Figure 3: Family geometry
Revit Family Library
On installation of every version of Revit, you will find it installs your country default content library locally to your machine. If you have several versions installed, then you will have a library for each version. To start out you can use these, but I would recommend copying them over to a server or cloud-based storage and change the default paths to the network. Thus, every user is accessing the same families.
Note: When creating any new families, think about in which versions they will be used. You don't want to spend a large amount of time creating one in 2019 then find you need it in 2017. You will have to create it all over again.
Many manufacturers have built their products as Revit families, which are generally available to download from the manufacturers’ websites or other product host websites like BIM Object (https://www.bimobject.com/), which now hosts all the content formerly on Autodesk Seek.
Family Creation Training
You do not need to be an expert in Revit to understand how to create or modify families, but a basic understanding of how Revit works is required. Then when you are creating or testing families you can understand how it should work in a project environment.
Now some people can learn by just having a go by themselves, but others prefer some formal training. You can search for your local Autodesk Certified Training Center here: https://www.autodesk.com/training-and-certification/authorized-training-centers
You will train with a Certified Autodesk Training Instructor at either one of the training centers or at your site in a traditional classroom format. This can be costly, but from my previous experience it is worth paying for.
Your other options are to buy a training manual from places like Amazon or local bookstores. Then have a go at learning by following the steps in the manual. Now bear in mind you won't get an expert to help you if you get stuck, and you will need to rely on colleagues or forums online to help you.
Alternatively, more and more people are considering online learning sites such as CADLearning, Global eTraining, or LinkedIn Learning. The training content is generally written by Certified Autodesk Instructors and these options offer support and can be cheaper than training at a certified training center. Finally, another option I highly recommend is Autodesk University online learning (https://www.autodesk.com/autodesk-university/). These are the classes hosted at many of the conferences Autodesk hosts across the globe and they are FREE.
Don’t be put off from creating your own Revit families—we all start somewhere. Just remember to plan it first by asking yourself a few questions. This will help you create the correct family type, geometry, and include the right information/data.
Good luck and happy family creation!