Hi. I want to be able to export the sum areas of different hatches to
show the total floor areas of different uses. Is there a good lisp
routine for this or any other way of doing this efficiently? I am a
complete beginner when it comes to this so please reply with an easy to
understand answer. Appreciate it.

Your question was answered over at the CAD Everything website.

There are free plugins to solve of this problem (to calculate the summarized areas of polylines):Polyline Quantities     https://apps.exchange.autodesk.com/ACD/en/Detail/Index?id=appstore.exchange.autodesk.com%3apolylinequantities_windows32and64%3aenMeteorSpec LT https://apps.exchange.autodesk.com/ACD/en/Detail/Index?id=appstore.exchange.autodesk.com%3ameteorspeclt_windows32and64%3aen