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Generate Building

The command Generate Building is available from the context menu of the area source. This command generates a building of a defined height with all facades and the roof covered with area sources (by default at a distance of 0.05 m off the facade). All sources will receive the same emission data as specified for the original area source where the vertical area source get addressed a directivity index of K0=3 dB by default.

  • First, insert a area source in the shape of the horizontal projection of the building.
  • Switch to the edit mode and double-click the area source. This opens the edit dialog.
  • Activate the Sound Reduction option and enter an indoor level, either directly or with reference to a spectrum. Enter all further parameters for this source, and click OK to close the dialog.
  • Then click the area source with the right mouse button and select Generate Building from the context menu.

In the Generate Building dialog, you can enter the parameters for the height of the building and, if required, the height of the terrain at the base of the building, and an absorption coefficient - either a single-number value or a reference to a spectrum (see Absorption Spectra).

Dialog options

  • Height of building relative (m): relative building height > 0 m
  • Height of ground absolute (m): After activation the absolute ground height at the location of the building polygon can be specified. The entered ground height effects the shape of the terrain depending on the settings on the "DTM" tab.
  • Absorption: After activation the absorption coefficient can be entered numerically or a spectrum can be selected via the file selector symbol from local or global absorption library. After selection of an absorption spectrum the spectrum's ID is displayed on this box.

When all boxes are completed close the dialog by OK. CadnaA generates

  • a building with a specified height – 10 m in this example,
  • the appropriate number of vertical area sources whose parameters are adopted from the first area source, at a distance of 0.05 m in front of the facades,
  • a horizontal area source at 0.05 m above the roof and
  • (in case) a surrounding contour line (see Contour Line) with the absolute height as entered.