Facade area is a pre-calculated property that uses the formula perimeter * floor to floor * levels. This is quite simple to compute for standalone building sections.
However, this becomes more complicated when geometries touch.
Giraffe will attempt to figure out where the sides of geometries should count as interior or exterior walls. The facade settings in analytics and urban control the function.
Urban | Analytics |
Click the cog next to facade area in the Urban metrics section. | Click the cog in the top right of analytics, then select Settings |
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Toggle on "calculate facade area" to enable the calculation logic to find touching faces.
Input a value for interior wall tolerance. This is how many meters apart a wall can be before it is not longer considered "touching"
For complex project, facade computation can cause reduced performance. Try toggling off "calculate facade area" unless you need the numbers for a report.