SEPP65 Extension


SEPP65 is used to study compliance of the model to solar access requirements in the NSW Government (Australia) State Environmental Planning Policy No 65 - Design Quality of Residential Apartment Development (SEPP 65).

The objective of the indicator is to evaluate if enough direct sunlight reaches the inside spaces of apartments, so for residential buildings. The calculation is performed for the 21st June (Winter), with a theoretical sky always clear.

Solar access requirements in SEPP 65 (from

Three design criteria set out measurable requirements for achieving this objective in apartment developments, as follows:

Design guidance set out under this objective provide supplementary advice on design responses that can be used to achieve this objective and criteria. One guidance deals with measuring direct sunlight:

DL-Light sketchup extension SEPP65 model snapshot image

SEPP 65 criteria or sun exposure analysis

The extension allows analysis according to two modes:

How To Use SEPP65 Extension

    Important: layers corresponding to glazing must be hidden to let the sun penetrate the spaces.

  1. Open SketchUp model. Follow recommendations to prepare your model for DL-Light calculations.

  2. Open SEPP65 dialog from toolbar df_dialog_icon or menu option Extensions -> De Luminae -> SEPP65 -> Activate extension and enter the parameters of the calculation.

    DL-Light sketchup extension SEPP65 main windows

    Fields description:

  3. Palette of false colours for the analysis.

    - For SEPP65 evaluation, the palette has 3 steps (colors can be customized). Every calculated surface is filled with the color of its status:

    DL-Light sketchup extension SEPP65 Panel tab

    - For sun exposure evaluation, the default palette has 6 steps corresponding to the 6 possible hours of sunlight during period. Palette can be fully customized.

    DL-Light sketchup extension SEPP65 Panel tab
  4. Selection of surfaces to evaluate:

  5. When results are imported, surfaces will have appropriate false colors and palette is opened. Here all visible surfaces are "green":

    DL-Light sketchup extension SEPP65 result
  6. Results analysis.

  7. For further calculations in the same model:

    DL-Light uses a calculation cache algorithm. It automatically detects if a surface requires recalculation or if a previous result can be reused. By default, the cache keeps the information of the last 10 calculations (value configurable in the preferences).

  8. Archiving results:

    DL-Light allows to archive all the results of a calculation: reports, textures and calculation steps (exported Radiance model, weather file, ...). This archive can be reloaded on the model, subject to using exactly the same model as during the calculation.

    See the page Archiving results for more informations about this feature.

  9. Snapshots:

    Current SketchUp model view with imported results can be exported with palette snapshot_with_palette_icon or without palette snapshot_icon to png format. To explore created images user can open folder where they are saved open_snapshot_folder_icon.
    This option is not supported in trial version of the extension (see licence information).

  10. Detailed analysis with the mode "Sun Exposure" has some differences:

    When "Sun exposure" mode is selected, the meaning on the model textures is different. The color around every sensor represent the validated exposure time for the sensor. A sunlight time moment is validated if at that moment at least 1m² on the surface is enlighted.

    DL-Light sketchup extension SEPP65 sun exposure details

    The tooltip information on a sensor is: validated exposure time for the surface, area covered by the sensor, validated exposure time for the sensor. Note: the Voronoi texture option may be usefull for the detailed analysis.

    DL-Light sketchup extension SEPP65 sun exposure details - tooltip
    DL-Light sketchup extension SEPP65 sun exposure details - tooltip

    Finally the report is different in "Sun Exposure" mode. The SEPP 65 result is not displayed, but statistics for exposure time of surfaces.

    DL-Light sketchup extension SEPP65 sun exposure report
  11. Preferences:

    The preferences dialog permits to customize further the SEPP 65 computation if needed.

    DL-Light SEPP65 extension preferences 1
    DL-Light SEPP65 extension preferences 2