How would I go about calculating the area of the analysis grid that is above a given threshold value. I know I can find the percentage of all points above it, but I need the actual floor-area and preferably very accurately.

This Ecotect script demonstrates how to iterate over the current analysis grid in your model and calculate the actual surface area that is above a given threshold, in this case the current minimum scale value. Whilst Ecotect can already show the *percentage* of grid points above a threshold, this script includes the fractional areas of cells that are partially above and partially below.