Design Options

Design Options


In this lesson, you will experience the process of identifying areas of a project where multiple design options are being considered and a workflow for exploring, evaluating and presenting those options within a single integrated design model.

The suggested exercises present two examples of varying scales:

  • Considering options for the design of an entire building wing.
  • Comparing alternatives for room layouts in a portion of a building.

Defining Option Sets and Options within Each Set

Designersoften explore many options and possible alternativesto particular design problems in their quest for the best design solutions. For example, designers might consider several options for:

  • Fitting out and furnishing an interior space
  • Providing a landmark canopy over the entrance to a building
  • Articulating the balcony railings on a prominent building façade

A BIM-based design process enablesdesigners to define key features or areas where sets of design options will be considered and manage the proposed options in the context of the overall design.  Designers can define as many options sets as needed to evaluate proposed design alternatives—there is no limit.

Rather than maintaining separate models for each of the proposed options, a single model is used to coordinate the design of all options. The main building model includes all the elements that are fixed—that is, not affected by the options being explored--and thus, acts as a backdrop in which the design options can be evaluated. This single model approach ensures consistency as the design progresses and continues to evolve.

Presenting and Comparing Design Options

Separate views are typically created that display each design option in the context of the main model for presentation to the design team, clients, and other stakeholders in the review process. These views can be presented individually or placed on a single sheet for easy comparison.

One of the options in each design option set is assigned to be the primary option or leading candidate among the options being considered.  By default, the features of this option are displayed in model views.  To easily see and consider additional design options, views can be duplicated and each view can be set to display a specific design option.

This ability to display the elements in specific design options extends to all model views included schedules. This powerful feature enables design options to be fully evaluated in both graphical and tabular views.  For example, one wall schedule can tabulate data for the primary option and another wall schedule can present the revised datafor a secondary option.

After the design options have been considered and the preferred option has been selected, that option can beaccepted as the primary design solution and moved back into the main model. When a design option is accepted, elements in the other design options are removed from the building model to reduce the file size and improve model efficiency.  This approach is recommended if you’ve made a definite design decision and intend to move forward with that decision. Keeping unused and out-of-date options in the project needlessly inflates the file size and adds unwanted complexity.

Learning Objectives

After completing this lesson, students will be able to:

  • Explore how to define new design option sets and experiment with design alternatives
  • Appreciate how to present each design option in separate views
  • Understand how to choose a design option as the final solution and discard the other alternatives


Using Option Sets To Compare Building Envelope Design Alternatives

In this exercise, you will learn how to:

  • Define option sets for the major design decisions and design options within each set.
  • Copy model elements into design options.
  • Experiment with design variations, by adding, deleting, or modifying the elements in each design option.

Figure 2.3.1 Defining an option set and placing model elements into play

Video Tutorial

Student Exercise

  • Create two new design options in the Auditorium option set to explore alternative designs for the auditorium space and building envelope.
  • Use these design options to illustrate two new proposed designsfor the auditorium that vary key features of the building envelope, for example:
    • Wall layout and materials
    • Window placement and glazing options
    • Roof design and materials
  • Create floor plan and 3D views showing each of the proposed design options for the auditorium and place them on sheets.

Figure view showing Option 2 for the auditorium

Using Option Sets To Compare Interior and Room Design Alternatives

In this exercise, you will learn how to:

  • Define option sets for the interior design alternatives and creating design options within each set.
  • Experiment with interior design variations, by adding, deleting, or modifying the elements in each design option.
  • Accept a chosen design option and discarding the remaining options.

Figure 2.3.3. Changing interior furniture layouts for Option 2

Video Tutorial


  • Create a new option set for the north end of Building 3 and three design options in it.
  • Add the currently defined interior wall elements and all furniture in this area to the set and choose only design Option 1.
  • Switch the plan view to show Design Option 2 and create a new layout that illustrates the use of this area as a computer-training center with workstations and desks.
  • Switch the plan view to showDesign Option 3 and create another layout that proposes a design for a new student lounge in this area.
  • Duplicate the plan view to create three views and set the visibility/graphic overrides to show each of the design options in a separate view.
  • Crop and scale the plan views to highlight the option set area. Place those views on sheets.

Figure 2.3.4.Interior model elements added to Option 1 of Interior Fit out Option Set


Using Option Sets To Compare Building Envelope Design Alternatives

  • What building features would typically be changed as we explore building envelope alternatives?

Some building features that could be explored through design alternatives include wall layout and materials, window placement and glazing choices, roof form and materials, as well as the design of terraces, exterior spaces, and entries.

  • How are elements that have been added to the options sets different from the main model?

As elements are added to option sets, copies of the elements are made in each of the chosen design options. This cloning allows you to make changes to the copied elements in each option independently.  For example, changes made to the copied elements in option 1 do not affect the copied elements in option 2. By contrast, any changes to elements in the main model appear in all of the design options.

  • How is the primary option different from the other design options?

The primary option is the one option that is displayed in views by default (unless a specific option is selected in the visibility graphics overrides for a view). This is often confusing for users, so it is typically better to create separate views and assign the design option specified in each explicitly.

The other key difference is that the primary option can be accepted as the choice for an option set and other options will be discarded. Before an option can be accepted, it must be made primary.

Using Option Sets To Compare Interior and Room Design Alternatives

  • Can hosted elements (for example, windows and doors) be added to a design option?

In order to add hosted elementsto a design option, the hosting element (for example, the wall) must also be added to the design option.

  • When design options are used, which elements appear in room, door, and window schedules?

Schedules are like any other view and display the elements determined by the view settings. If a design option is specified in the visibility/graphics overrides, the elements in that option will be displayed in the schedule. Otherwise, the elements in the primary option for the option set are displayed.

Key Terms

Key Term
Option set
A collection of design alternatives that focus on a particular aspect or feature of the design.
Design option
An alternative design solution for a specific feature or problem. Design options are grouped into option sets.
Active option
The design option that you are currently editing. Elements in other options are hidden from view.
Primary option
The currently selected default design option, which is displayed in views by default (where a specific option has not been specified).