Schedules & Quantities

In this lesson, you will explore ways of creating tabular views called schedules and summarizing information about the building elements through groupings, sorting, and calculating values.

One of the key benefits of the BIM workflow is the ability to manage not only the drawings, but also the tabular information in the project database. With BIM we can dynamically generate and update schedules of building elements to support many purposes, for example:

Since the information flow in Revit is bi-directional, the data from changes in the model flows automatically into the schedule, and changes in the schedule automatically flow back into the model. The model data can be edited through our schedules, and this technique should be used when it is easier or more efficient than doing so selecting and changing elements in graphical model views.

A schedule presents a tabular view of the project data, which can be filtered, grouped, and formatted to fit your needs. Schedules can list every instance of the building elements or collapse multiple instances into single rows, based on the schedule's grouping criteria. Since Revit software creates a database of the elements, building a schedule is very similar to creating a database query.

Schedules should be formatted to meet the needs of the end-user, whether they are engineers, designers, clients, or code officials. Schedules are often placed on sheets either alone or accompanied by the corresponding model view. Finally, schedules can be exported to many formats, including delimited text files compatible with spreadsheet software and database formats.

By adding information, or “intelligence,” to schedules, we optimize the workflow and maximize the utility of the building model. In this way, enhanced schedules can be the basis of analysis for many goals of project.

Since model elements store all information about their physical properties, we can add information fields or parameters to model element types--for example, type mark, size, material, fire rating, and any other custom data fields we need. These parameters can be either user entered, such as text fields, or calculated values that depend on other parameters.

Adding calculated values to schedules avoids the errors and unnecessary time spent performing manual calculations. A simple example of a calculated value formula would be a width parameter set to equal twice the height of an object. In practice, formulas can be used in many ways, both simple and sophisticated. For example, formulas can be used to:

Formulas support the following arithmetic operations: addition, subtraction, multiplication, division, exponentiation, logarithms, and square roots. Formulas also support the following trigonometric functions: sine, cosine, tangent, arcsine, arccosine, and arc tangent.

The valid formula abbreviations for arithmetic operations and trigonometric functions include:

You can enter integers, decimals, and fractional values in formulas, using normal mathematical syntax, as shown in the examples below:

Lastly, we can even introduce conditional statements to our schedules. A conditional statement uses the following structure: IF (<condition>, <result-if-true>, <result-if-false>). And it means that the values entered for the parameter depends on whether the condition is satisfied (true) or not satisfied (false).

Conditional statements can contain numeric values, numeric parameter names, and Yes/No parameters. You can use the following comparisons in a condition: <, >, =. You can also use Boolean operators with a conditional statement: AND, OR, NOT. Currently, <= and >= are not implemented. To express such a comparison, we can use a logical NOT. For example, a<=b can be entered as NOT(a>b).

The following are sample formulas that use conditional statements.

After completing this lesson, you will be able to:

You cannot change an element’s model category from within a schedule, but you can change its family and type if these fields appear in the schedule. Family and type typically appear as drop-down menus listing all available types currently in the model, so new types can be selected from the menu in the same way they are selected using the Type Selector.

Schedules are live model views that are dynamically updated as changes are made to the building model. If you want to save a static snapshot of the schedule data at a particular point in time, you can export it as a delimited text file.

Yes. Each row in the schedule represents a building element in the model. You can select a row, then right-click to access commands that let you show or delete that element.

Yes. You can and should standardize your schedules between projects. You can used the clipboard to copy and paste schedules between projects. Or you can add a schedule to a project template file to automatically include it in new projects.

Many answers are possible. Calculated values provide great flexibility to compute the numbers of greatest interest for each discipline involved in the project.

For example, construction managers often focus on project costs, so calculations which tabulate the total cost of building elements or summarize square footage cost estimates are typically useful to them.

Similarly, schedules with calculated values can be used to compute percentages and values needed for LEED analysis and certification – for example, estimating the water or energy savings available through high efficiency fixture selection or innovative alternative design strategies.

Schedules in Revit can be used to compute key quantities, but they typically do not provide the level of detail needed to create a complete material take-off. The tools available in Autodesk Revit focus on modeling the building information and supporting design tasks.  The information in the building models created can be used by other software solutions, for example Autodesk Quantity Takeoff, to perform a more detailed analysis and quantification of the design.