Support site for Simplebim® users
In This Topic
    Space Boundary
    In This Topic


    Space boundaries are special relationship objects in IFC that connect a space to its bounding elements (walls, doors, windows, slabs). The relationship also has a 2D geometry that represents the 'boundary plane' between the space and the bounding element. If a side of a space does not have a bounding element a virtual space boundary is used.

    Architectural design applications, such as ArchiCAD and Revit can export space boundaries to IFC, but the data has very uneven quality.

    Space boundaries are used primarily by energy and indoor condition analysis applications.

    Functionality of the Add-on

    Preparing Models

    It is important to make sure the model is suitable for space boundary generation before any space boundaries are generated. The add-on allows for a fair amount of modeling inaccuracy, for example a space and wall do not have to meet each other perfectly accurately, but it can't do miracles.

    Resolving internal/external for building elements

    Space boundaries contain information whether the boundary is for a internal or external building element. The add-on gives the following options for determining this status.

    Installing and Running

    1. Download the installer from
    2. Run the installer. Please note that you need administrator rights for running the installer
    3. Import your model
    4. Take the steps for preparing your model as described above
    5. Run the Create Space Boundaries tool. You find instructions for running tools here.
    6. Set the tolerance and create the space boundaries
    7. Export the model into a new IFC file. 
    When you export the new IFC file, be sure to first include the Space Boundaries in the IFC Export Options. By default space boundaries are excluded from the IFC export because they are needed by so few applications.

    Known Limitations