Area of multiple polyline objects, 2009

Using 2009, We have drawings with polylines drawn around each room in the building. We use these drawings to know the square ft.of each room. periodically we need to add up a collection of these rooms and provide (for example) the sqft used by different departments. These rooms might be scattered through the building. There are hundreds of rooms of various sizes. Can anyone explain how to Select/add/accumulate??? the areas of multiple objects without error. Also some of these rooms might have a small room within it to be subtracted out of the sqft. An explanation of "how to" or point to a link for tutorial would be much appreciated.

Thanks, cadmatic

1st step search here polyline area lisp or vba

2nd multi polyline areas

3rd I think you may have to figure out the final answer subtract polyline ?.

If you set the polyline boundries of the rooms all on one layer, named boundries.

it will make it a little easier. You will be able to turn off and lock other layers.

Then select all, list>enter this will give a complete listing of the areas.

Don't know how much that will help.

Thanks to all, I'll explore these options.