How to create an environment with Sketchup

Thanks. And what components would they need to delete? By the way, when I went to the purge screen and did what you wrote I didn’t see anything happen.

Say you created a component (A).
At certain time you may have a better component (B) and and decide that (A) needs to be replaced by this new one (B). Or you just delete (A) from modeling space for some other reason, whatever.

(A) seems to be gone but it is still available (unlike a deleted group) in the ‘In Model’ component browser. (You may want to reuse (A) later). Even unused it takes up memory space. ‘Purge unused’ (see(*) below) deletes the unused components permanently.

(*) To see this happening see:
Model Info > Statistics > purge unused. The listed materials, layers and components may drop, meaning some were not in use anymore.
All three local ‘purge unused’ options (per layer window, material window or components window) do make purging visible too.

A good example of when you need to purge would be when you are using things from the 3dwarehouse.
You download a chair or a house or a car etc and decide you don’t want it so you delete it. It is still there until you purge the model.
So you can have a a model that has almost nothing visible in it, but the file size is huge because it is storing all the models (and their materials) you downloaded and discarded.