I have one Polygon-Layer with land-parcels and one Polygon-Layer with buildings. With the Overlap-Tool I can easily calculate, what area of each parcel is covered by one or more buildings.
But I need to calculate, how much living-area was built on each parcel. The living-area per parcel may be part of several buildings. And the buildings may stand on several parcels. In this case I assume that the living-area per parcel ist proportional to the part on each parcel (thats why overlapping comes into play).
So my idea was to calculate the overlap of the building-layer over the parcel-layer but somehow weighted by the attribute "living-area".
So e.g. parcel A includes 100% of building 1 with 100sqm living-area but only 50% of building 2 with 200sqm living-area. So the total living-area on parcel A is 200sqm.
So how can I calculate the living-area per parcel with QGIS?