ArchiCAD Insights: Design Options

14 Aug, 2005 By: Kurt Ameringer Cadalyst

Option technology helps define multiple design variations within one project.

The Problem
Designers often must offer multiple design options throughout the design phases of any given project, including:
  • The size, type and style of building elements
  • Exterior and interior elevation styles
  • Floor-to-floor heights or roof angles
  • The number of openings, elements or rooms
  • Level of furnishing or luxury
Since the designer must create and present each variation separately, the use of design options means a great deal of manual work. Historically, designers were limited to the following options:
  • Use multiple layers containing different variations and switch these layers on and off manually.
  • Reference or merge complex files into the project and replace these links as necessary.
In either case, creating and maintaining presentations for each variation is cumbersome and time-intensive.

Overlapping options. To make matters more complex, some options overlap the same space or elements. When an element is affected by two options (for example, a bathroom layout and finish are two separate options), the number of variations for the individual elements increases dramatically. Until now, no BIM application offered a solution for this problem: you needed to created and manage each option individually.

Large options. A further problem arises if an option affects the whole building (for example, an option that spans multiple floors or different story heights). In this case the designer must create a completely new plan and add all the existing options for the new story level. This situation can result in an excessive amount of information and unmanageable file sizes.

The Solution
The Graphisoft ArchiCAD Option Manager makes it possible to create and manage overlapping options within a single model file without the use of layer combinations or references or modules. The variations among options may affect every attribute or parameter of any element within a predefined area or even within the whole project.

Different options can affect a particular element in different ways. For instance, one option can refer to the position of the element; another to its style or type; yet another to its material. There is no limitation on the number or type of parameters or attributes that can be changed within an option.

Explore different design ideas. There is no need to store design variations in separate files. The software records and evaluates different variations of an option; ultimately, you can keep only the chosen idea.

Doesn't significantly increase file size. Design variations record the actual state of the project and store only the differences from other variations (not the elements themselves). You can apply options to the whole project without having to remodel all affected elements and store them on separate layers.

Easy to set up, control and maintain. You can easily set up options and variations in the Option Manager palette. The definition process is very much like taking a snapshot of the project, and you can update or delete these snapshots at any time.

Handles overlapping (or nested) options. Several options may refer to the same elements. You do not need to model the combinations of such options, which radically decreases modeling work. (For example, three options with four variations each require only the minimum number of modeled situations; no need to model all possible combinations.)

Definition and control of the relationship between the options. Option Scenarios let you define simple rules that direct the behavior of option variations. Some variations may exclude others, so you can define packages of options.

Create Options
You create an option by defining its region using ArchiCAD's Marquee tool. The option will contain all the elements either partly or entirely included in the defined region -- even those from the hidden layers of the project.

Click the New button under the Option List window to produce the New Option dialog box (figure 1), where you can set the following properties:

Figure 1. Set your option's properties in the New Option dialog box.

Category name. Enter the option's category name. If you enter an existing category name, the option appears under that category. If you enter a new category name, the program creates the category and places the new option under it. You can edit the option's location at any time by dragging it to another category on the Option Manager palette (figure 2).

Figure 2. The Option Manager palette.

Option's name. Enter the option's name here. (Options must have a unique name in the project.)

Stories affected. If you used the Multiple Floor (thick) marquee method to define the option, you can extend the option's vertical size to the whole building with this checkbox. If you used the Single Floor (thin) marquee method, this checkbox is not available.

Save zoom. This checkbox saves the current floor plan location and zoom level with the option. The program automatically uses this location and zoom level every time you activate the option.

Save display options. Use this checkbox to save the settings from ArchiCAD's Display Options dialog box (Display Options and Display & Output Options). The program automatically uses these display settings every time you activate the option.

You can define the marker pen and line type when creating an option. To modify the properties of an existing option, activate it and click the Edit button to open the Option Settings dialog box.

A variation is a snapshot of the elements belonging to the option. The program stores only the differences between each variation. This way other options can affect the same elements later. Variations also can save a description of the elements, a preview image and a URL link (figure 3).

Figure 3. Variation settings.

Sometimes it is necessary to create links between different option variations -- either an inclusive or exclusive link. To create a link, use the Scenarios button from the Variation Tools dropdown list to open the Option Scenarios dialog box. To create a new rule, press the New button in the Option Scenarios dialog box, enter a name for the rule, and decide whether to make the rule exclusive or inclusive (figure 4).

Figure 4. Creating a link between option variations.

Exclusive scenario. In the exclusive scenario, the option variations defined in the first part of the rule prevents you from selecting the option variations defined in the second part. (The reverse is also true: if the conditions defined in the second part are active, this prevents you from selecting the variations defined in the first part.)

Inclusive scenario. In the inclusive case, if the condition defined in the first part of the rule is true, the option variations selected in the second part become active.

Error in scenarios. If you define a new scenario that conflicts with an existing one, you receive a warning message, and the new rule is be deactivated. Similarly, if a newly defined scenario results in an infinite loop, the new rule is deactivated by default.

Import and Export
Once you have created and selected your options, you can export the status of the options (i.e., the active variations) to an external file. The Import command lets you load this file later into the same project. This switches all the options to the saved variations, which is useful for storing different option combinations or to save a client's selections for later use.

Given the number of options often required in the design process today, the availability of a solution to assist management of the data allows more time for you to focus on design and spend less time managing the process.

About the Author: Kurt Ameringer

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