Day 7

In today’s lesson, we learned how to work with and modify families. There are three types of families:

systems families

These families are preloaded into Revit and cannot be created or loaded into Revit.  These include walls, roofs, floors, levels, and dimensions.  You can create different types of these families but the system itself cannot be recreated or changed. 

component families

Component families are template based families loaded into projects which are comprised of different configurations of model components, annotations, symbols, and sizes.  These can be created or loaded into Revit.  There are many standard family templates that can be edited to change components sizes and geometries.  In order to make the component a standard component, you must save it as an external RFA file and save it to your standard template.

Parametric

in-place families

In-Place families are created and modified families which are saved to a project.  These are then used within the project they are created and do not exist beyond it.  If you do not believe that you will need to use the component beyond the project, then in-place components would be the best thing to use.

Creating Component Families

Parametric values define family types.  An instance parameter controls the single account of a family type i.e. one door. When you modify an instance parameter, you change one element.  A type parameter controls all instances of a single family type. When you modify a type parameter, you change the parameter for every instance in the family type.

Component Family--->Type Parameter--->Instance Perimeter

Parameter Characteristics – when you create a parameter, you specify a discipline, type, group, and whether it is a type parameter or an instance parameter.

Family Editor 

The family editor is the tool in which you can create component families. To open the family editor, you must either choose a template in which to work off of or select a family and press edit family on the options bar.

The family types dialogue box found within the family editor helps define a family type by creating geometry of the type, by defining type parameters, and by flexing the family type. To define the type parameters, you can associate dimensions with a certain parameter or you can define parameters based off of formulas in the types dialogue.  In order to correctly use reference planes, you should draw the planes and associate a certain property, like length, width, or depth with them.  You can then constrain or align the element with the reference planes.

Family Types Toolbar

Parametric formulas can be created in family types dialogue box and calculate value of a numerical parameter.  The formula is a parameter calculated through the use of other parameters, like Depth = Width/2.  These formulas can utilize addition, subtraction, multiplication, division, and some trigonometric functions.  These formulas are case sensitive, however, so be aware of that.  You can also use conditional formulas which establishes relationships betweens certain conditions like:

if (<condition><result if true>, <result if false>)

Formulas can utilize <,>,=, and and/or/not statements.

 

Step by Step Guide to Creating Component Families Define the category of the family by selecting a template, which defines the way the family can be used  (ex. select a door template to create a door family) Create reference planes and add dimensions between.  You can use references planes in order to set height, width, depth, left/right or front/back distances, and sizes of subcomponents.  Create parameters in order to define values for elements in family, such as widths, lengths, heights, and other parameters.  These are assigned values of elements which are used in order to define the element as well as create new types within the family, Assign labels to dimensions to associate them with parameters. Flex the family and add the 2D AND 3D geometry (flexing the family is the method of changing the parameters in order to ensure that element components are defined correctly). Assign geometry to subcategories, like door hardware on a door, and assign parameters the elements can associate with.  Some parameters can include materials, Yes/No circumstances, and dimensional parameters.  These parameters will link the subcategory to the component family. Associate symbolic and model lines with a subcategory which can be done using the type selector list or using element properties. Define types in families, which are based upon size, materials, or subcategories. Save the family and load it into a project. Verify the family if working correctly in each of the views.

Creating Nested Families

A nested family is a component family that is loaded into another component family.  The main family is the component family in which hosted the nested elements.  When a nested family is loaded into the main family, its properties like its definitions, materials, hatch patterns, subcategories, and parameters become available in the family. An example of a use of nested families would be if you have a door main family and want to add things like door hardware, trim, etc. to create an entirely new component family. 

In order to link nested families you must add parameters in the main family in the family editor bar.  You can do this by aligning and constraining the nested components to the main family and linking their parameters together.  You can nest different types of families in to the main family in order to create different types of the family. For example, you can add in many different door families into a cabinet family to create different component types.  To control the visibility of the component, you must create a parameter in order to control the visibility of the element.

GUIDELINES TO CREATING NESTED FAMILIES

• decide the host family into which you are going to load the nested families or create a new family from a template
• test a nested family in order to make sure it behaves correctly (to do this mess around with the dimensions to see if its linked with the main family)