What is Revit Family Creation and How to Work On It?

Autodesk Revit is one of the most distinguished and long-used architectural design and documentation software used by BIM and digital construction professionals. With the help of Revit, construction modeling professionals are able to create Revit Families that aid in a greater level of collaboration and high-efficiency execution in the process of construction modeling.

Revit Families can be easily created with the help of Revit Libraries. These Libraries are immersive data resource environments in Revit allowing AEC professionals to not just easily create the basic parametric families for these elements, but also aim for standardized and consistent designs that are flexible and easy to adjust.

What are Revit Families?

Revit Families are basically the collection of similar items that have common behavior, look, and working parameters. These Families may include the different building parts and components of walls, doors, furniture, equipment, and fittings. Revit families also have annotation elements like door tags, elevation symbols, and column gridlines.

The best part about Revit Families is that these are available in a pre-built format in the platform but can also be customized with tailored specifications. This creates possibilities for adopting different design options and creating diverse construction frameworks for building projects.

Revit Families can be saved and stored to be referred to and applied in different projects. This significantly helps in cutting down the efforts and optimizing the time at the job by creating standardized family templates. Revit Families allow project professionals from different functional disciplines working across different construction phases to closely collaborate and execute projects with great ease and accuracy.

What are the Different Types of Revit Families?

There are three different types of Revit Families namely, system families, loadable families, and in-place families.

System Families

The System Families are the basic elements that are to be assembled on a construction site. System Families include Floors, Walls, Ceilings, Ducts, and Pipes among other building components. These are already defined in the Revit User Interface and can be used as they are without doing any alteration to their existing style or form.

Loadable Families

Loadable families are also called component families. These typically include components that are purchased, dispatched, and implemented in a building. Loadable families may include various building components that need to be installed after the structures are built. For example, Doors, Windows, Vents, Exhausts, Water Heaters, Furniture, Plumbing Fixtures etc. These families are defined by users and can be altered as per the requirement of the project.

In-place Families

In-place families are the custom families that are created in Revit to meet a particular requirement of a project. They use the same Revit Family editor as used by System and Loadable families to create or edit components. In-place families are specific to a project and do not allow creating multiple 'Types' and cannot be saved as external RFA files. It allows creation of custom free-form objects serving the specific need of the project situationally serving the context.

Revit Family Creation - How to create a Revit Family?

As we know what basically Revit Families are and how they are placed in the realm of construction planning and implementation, let us explore how Revit Families are created.

Get started with the basics

First of all, it all begins with giving a thought to how you would like the families to behave and how the users interact with the Families. Go hands-on with painting families with this thought process and make sure you get it aligned with your core purpose.

Select a template

Choose any free Revit families template from the options available if you have any ideas in mind. Otherwise take up "Generic Model Face Base”, which is the most commonly used and a favorite general choice most of the time.

Build a skeleton

Construct a building skeleton by drawing right and left reference planes. Snap it at the center origin point with the aligned dimension tool, then do the same for front and back.

While doing this, make sure they are placed at an equal distance. Also, give them unique names so it is easy to recognize them all the time.

Keep track of everything that is going within the project. Make necessary adjustments whenever required to keep it going smoothly.

Get a pencil and start drawing

Once you have the initial plan in place and you are sorted with your basic templating and block-building stuff, it's time you should actually get started with real execution.

Lay the foundation

Create the base family by using the extrusion tool. In order to flex the model and for the locking of the sketch lines in the reference plane, go to the lock button and select the reference plane in which it is required to be trimmed back into the position.

Use a different view to edit

Define the elevation of the building creating a height reference and thickness reference plane. In this process make sure each plane has its own set of parameters. Don't forget to check and lock the geometry.

Make the sub-families to be used under parent

Create the subsidiary families to go under the parent categories of families by incorporating new skeletons, shapes, and reference planes.

Make a new skeleton

You may do this by creating a whole new family or just by using a generic model template. By using a template you won't be bound to make it as per a certain face. If you are repeatedly implementing a face, you should better go for nesting, this will considerably save you the execution time.

Draw a shape

Draw the objects of a fixed cross-sectional profile and properly align them with the planes to create the shape of subfamilies. Once a sub family is created, put it on a parent family and apply a radius label to keep its reach and periphery under regulation. Once this is done, choose that particular label and create and assign a new parameter to it.

Incorporate reference planes

Define and create the reference plane height and put a lock on the top end and the bottom end of the plane, just as it is done in the case of the parent family. Once the top and bottom are locked, test it and make the adjustments in the family to match the table height and legs.

Add a diameter parameter

A diameter parameter is added to be ultimately controlled in the parent family as there may be a requirement by a few users to refer to diameter. Here, adding a new formula (diameter/2) is needed to reduce the results to half of the original dimensions.

Assign a material

Assigning a material to the parent family is important to get better control of the design.

Draw support pieces

The brackets that are placed to support table tops are one of the examples of support pieces. Do some basic detailing and define the support pieces to add them as a point of reference but don't go overboard.

Include other families as a member of the parent

Other families need to be included as members of the parent by going to the parent family page, including reference planes, and making changes to the added family.

Go to the parent family page

Add the leg family that has been generated lately to the family mix. As the geometrical values of this may be restricted to certain behavioral responses, creating the best-fitting instances of it and applying it aptly is important.

Include reference planes to help with multiple family placement

The reference planes need to be placed at the right, left, back, and front of the room. These planes basically decide where the table legs will be positioned and placed as per the table's perimeter. This can be done by assigning the same perimeter parameter to the table legs. Once this is done give it a name.

Alter the added family

You may associate the parameters of the nested families to the parent family by making a selection in Revit software. This means that you do not have to select each nested component and edit it separately, rather you may assign discrete parameters to the parent family and do the needed editing there.

Add a new parameter to the list

The dialog box asks about where the parameters need to be associated. Here, the naming needs to be done following the same conventions, however for parameter labels, "leg" should be added at the end to distinguish between the types of parameters. To avoid adjusting the height of the table against the height of the leg, make sure everything is properly labeled.

Make sure the size is right

Add a formula to make the table leg report to be able to depict the table’s height measuring the thickness accurately.

Finalize the Revit family design

Assemble All Components

Place each component, such as the legs, in the correct positions, repeating the process for uniformity. This will ensure all four legs behave consistently. If desired, you can swap in a different leg style for variety. To enable switching between families, label each nested item, then create alternate leg styles by modifying and saving the family with updated attributes. Replace the original legs with the new versions to finalize.

Modify the family using parameters and constraints

With the table structure set, consider adding additional parameters and constraints to ensure practical dimensions, like preventing an oversized 300-foot table. Test these values to verify proper functionality.

Integrate parameters with constraints

Align parameters with constraints to maintain stable geometry when conditions are unmet. Apply this approach to nested families as well. Make sure constraint parameters are incorporated in formulas, as formulas won’t work correctly without them.

Test the family design

Test the family thoroughly to confirm everything functions as intended. This needs to be done especially if the file will be shared with others.

Create pre-defined family types

Define a few family types to reflect design intent and various versions. For families with more than six variations, create a type catalogue (.txt file) to organize them.

Finalize material selections

Apply tabletop parameters and materials, using generic options as needed. Render the materials to improve visual presentation.

Clean up the display

Hide the host in the family views to tidy up preview images. Save the file with a "3D View: Preview" setting to complete the process.

Put your new Revit family to test

Once you are done with unfolding it at the base level and creating the action framework of it, create a new project, import it, and put it into the test.

To Conclude

Revit family creation is one of the most essential aspects of Revit architecture as Revit families work as basic building blocks for any BIM modeling project. Revit families not only save a lot of time in creating BIM objects and elements but also provide consistency and unanimity throughout the process of building modeling and construction documentation.

This entire article covers different steps and practices for creating different types of families, putting together components, and aligning process workflows to get the most value out of Revit family creation. Implementing this right as per your project situation and requirements, you may get to save the most out of cost, time, and effort, while getting optimum output from the project.