Logo Onuma Inc.
 GSA BIM Guide and Onuma
Architecture Services - Solutons Products

Products > GSA > GSA BIM Guide



appendix c - product specific instructions

Following are specific instructions and recommendations on how certain functions can best be performed when using various BIM authoring tools. At PBS’ request, the information provided specific to each authoring tool has been confirmed or provided by the vendor. Below is the company information for each contributing vendor, including information about how to contact each company for responses to any questions or comments:

ONUMA System™

ONUMA System™ has been designed to capture architectural planning decisions throughout the various phases of a project in a BIM. This web-enabled planning system can be implemented from the earliest stages of planning to the more developed design phases. Its functions even extend all the way through to the facilities management of the completed structure.

The creation of a BIM can be often times labor intensive. This web-enabled tool is preconfigured to export an IFC of a Building Information Model in accordance to GSA’s IFC Spatial Data requirements. The tool has been designed to achieve these results with minimal effort and training.

A-2-1- Installing/Enabling IFC BIM Import/Export

_Some BIM-authoring applications include IFC BIM import/export as part of the product; while in others it is available as a separate module. More information is available from each vendor below._

ONUMA System™

IFC export comes standard with the ONUMA System™. This is a web-enabled tool which simply runs from a web browser. No special software or plug-ins are required to implement IFC export. GSA specific IFC settings are preconfigured in the ONUMA System. Users have the ability to view and edit GSA Specific data directly in ONUMA System™ prior to exporting IFC.

A-2-2- Saving/Exporting IFC BIM Files

_BIM-authoring applications have different ways to store (export) an IFC BIM file. Either there is a separate tool for this purpose or the BIM-authoring application’s Save As command is used to select the appropriate IFC BIM version._

ONUMA System™

There are two main methods to output an IFC file from ONUMA System™.

Method 1: IFC Output from the Project & Scheme List

This method should be used if a user wishes to quickly generate an IFC file without having to “open” the project. From the list of Projects and Schemes, click the Export button.


NOTE: The user interface above illustrates how access to the database and export of IFC files can happen at an entire portfolio level or down to an individual building level. With this interface, a user can quickly generate IFC files of multiple buildings without opening up the file itself.

Typically the process of exporting IFC files can be very time consuming. This is further compounded if multiple IFC files need to be generated at one time. Saving out an IFC file from the ONUMA System™* can take as little as 30 seconds. For a larger building such as the GSA HQ Building, the IFC export took approximately 1 minute. The IFC file size is only about 3MB.

After selecting the Export button, the Exporter window will pop up. Select the building to export from the list under “Buildings”. Then select IFC from the file format pulldown. Click Export.

Note: The ONUMA System™* allows users to export all the data for the building or only specific data points (see image on right).



Method 2: IFC Output from a within a Scheme

This method is similar to Method 1 but applies if a user already has a project opened. Click on the button Export. The Exporter pop up window will now display. From here, follow same instructions as Method 1.


A-3-1-Modeling Spaces

The follow section explains the recommended methods for modeling spaces to be exported as IFC Space (IfcSpace?) objects.

Onuma System™

All spaces created in ONUMA System™ can be output as IFC Spaces without additional set up.

There are 3 ways to add spaces

  • 1.Add Empty Space
  • 2.Add Template Space(s)
  • 3.Add Shared Spaces(s)


Method 1: Add Empty Space

Click on button Add Empty Space. A brand new “blank” space will be added to the Scheme. This space will not have any furniture or equipment populated in the space.


New “Empty Space” created

Method 2: Add Template Space(s)
Click on button Add Template Space(s). A Modulet window will pop up.


This unique feature in ONUMA System™ enables a user to populate their scheme with Template Spaces that are provided in ONUMA System™ or created by the user in other buildings, schemes and projects.

Method 3: Add Shared Space(s)
Click on button Add Shared Space(s). A Modulet window will pop up.


This unique feature in ONUMA System™ is extended to allow users to leverage Spaces that have been developed by other users who have elected to “Share” particular schemes they have worked on. This is particularly effective in teamwork environments where several people can benefit from the work effort a one person.



In addition to adding spaces using this method the spaces that have additional data such as furniture and equipment will carry that geometry and data with it while adding spaces. In this way a user can quickly populate a building with spaces that match requirements.

Editing Spaces Editing spaces allows the user to change the shape of a space and the size, move furniture and add new furniture and equipment. Square spaces can be changed to L shaped, U Shaped or user defined shapes.

Select Edit Spaces on the pulldown above the list of spaces.

Now “grips” will appear on the Spaces. These can be used to adjust the size of the Space. Dimensions will dynamically update as the geometry and area of the space are updated.


Click on the “grips” to edit Space.

A-3-2-Copying Spaces

When copying a space in a BIM-authoring application the user must ensure that the Space Number is updated for the copy so that each Space Number is unique. Vendor –specific instructions are presented below. Onuma System™

Spaces are copied by clicking the Add Template Space(s) or Add Shared Space(s) in the Onuma System (see section C-3 Modeling Spaces for additional information on using the Modulet). In addition to being able to copy Spaces within the current project ONUMA System™ can query and leverage all Spaces within any other projects that the user has inputted into ONUMA System™.

The Modulet is used to navigate through the list of projects. The user can then select the space(s) to copy over into the current project. The user can then use the Space Settings Matrix to re-number the new space(s).


NOTE: Since ONUMA System™ operates as a web-enabled model server, users can leverage spaces in ANY project that they inputted into ONUMA System™. In a networked environment, users can also share Projects and Schemes, further increasing the availability of spaces that can be copied into a project

The database in ONUMA System™ will keep track of all Spaces that are added or deleted from the project. The Space Settings Matrix is used to edit room numbers.



Copy spaces using the Modulet

ONUMA System™ will warn users of any duplicated Space Numbers. As the design progresses and develops, the importance of avoiding to have duplicate Space Numbers increases.

ONUMA System™ will also warn users of space names that do not match GSA standard naming conventions. In early planning studies when importing a list of spaces into ONUMA System™ from an Excel file, the system can automatically flag non standard spaces and give the user the option to rename them to match GSA standards. In later stages of design if an existing IFC model is imported from BIM Applications, ONUMA System™ can also flag and check for inconsistencies.

A-3-3-Mirroring Spaces

Mirroring functions in some BIM-authoring tools may cause problems when IFC BIM export is used. Vendor specific instructions to avoid such problems are presented below.

ONUMA System™

Any space added in the ONUMA System™ can be mirrored. Choose Yes or No on the Mirror Y pulldown. The mirrored spaces will export to IFC correctly.


A-3-4-Columns and Shafts in Spaces

In some area calculations, columns and building services shafts shall be excluded. Effectively, this means that spaces surrounding large columns and shafts will be modeled as if they had holes or voids, from a space calculation point of view. This function is accomplished differently in each of the major BIM-authoring applications, as described below:

Onuma System™

Although ONUMA is more focused on the data related to the spaces with respect to planning and less on the physical modeling of all the detailed components of a building, it will capture all the spatial data generated from other IFC compliant applications that took items such as columns and shafts into consideration. This is an example of how ONUMA does not require its users to get down to detailed modeling in the tool, yet still leverage detailed data from other BIM applications using IFC. This ability to capture BIM data at different levels of detail is one of the strengths of the ONUMA System™. This is useful because often times during the preliminary planning and programming stage, one may not even know which portion of an existing building the project will go in or even if some new construction is required. This means specific architectural elements like columns or shafts are unknown anyway and could not be modeled.

In the interests of leaving options open for the end users, future versions of the ONUMA System™ will allow Schemes to be populated with a “Column” and “Shaft” object that willl reduce the area of Space it is placed in.

Space Number Space Name

A-4-1-Space Number and Space Name Fields

The information content of a BIM is very dependent on the BIM authoring application being used. This Guide shall be applied in design work insofar as is feasible with the BIM authoring application. Software specific instruction shall be followed whenever available.

Defining Space Number and Space Name in the included BIM authoring applications:


A-4-2-Area Calculations

There is various output Reports that provide area calculations. ONUMA System™ is also very flexible at providing this area calculation in conjunction with any other data relating to the spaces that have been inputted. For example, it is easy for a user to review the Space Name and Number along with the area calculation and any other data field the user wishes to review at the same time.



ONUMA System™ captures the Space Name and Space Number Click on the button Space Settings Matrix. A pop up window will display a list of Spatial Data.


Users have the ability to select specific fields of data they wish to review and/or edit. This data is structured in accordance with the GSA IFC Spatial Data requirements.

Click Proceed after checking off the data fields

A Space Settings Matrix will pop up.



This matrix is organized by Space Name and Space Number.


GSA Space Standards as well as other GSA Spatial Data Attributes can be viewed and edited in this Space Settings Matrix

2010-02-08 14:01:46