Projected Skin Areas

[poco2013]

I need to use the "Net Skin Area" within a expression in order to calculate some quantities.

The parameters: Projected Component/skin area and Exposed Area are available within the Parameter groups- Components and Surface which make these areas available within the interactive schedules.

However, these groups, therefore properties, are not available within the expression properties.

Is there some other way to include these properties within a expression so that i can calculate wall quantities i.e. bricks and siding - for a multi-skin wall.