Groups and Sub Groups?

I started to model my house, creating Groups for each stage. Later on after seeing a SketchUp video, I learned that you could see your groups in the Outliner view. I seen that some how I created a Sub Group. Possibly not knowing that I did it.
Do I need the Sub Group?
Can I remove the Sub Group?
Why and When is it a good idea to use a Sub Group?Second Floor Base and Walls.skp (304.2 KB)

Likely you created a group and then while it was open for editing, you selected the geometry and made a group again. There’s generally not much if anything to be gained with what you have currently and you could get rid of one of them. I would be inclined to explode the inner group in each case. Right click on it in Outliner and choose Explode.
Screenshot - 11_21_2020 , 6_10_23 PM

Might help to think about making a group or component as putting what you’ve got selected into a container. Think of a sandwich in a sandwich bag. What you’ve got with your first and second floor groups is double-wrapped sandwiches. The extra wrappers in this case don’t really add anything but in order to get to the geometry to make any changes, you have to open both of them.

The place where this can be useful is when you have a number of groups/components that you wrap up together. (Two individually wrapped sandwiches and a bag of chips in a paper lunch sack.) This becomes a nested group or component. That can make it easier in some respects because you can selected one thing, the nest group and move all of the contents at once. Of course you still have to open the lunch sack and the sandwich bag to get at the contents to make any changes. Use nesting deliberately and sparingly so you can keep your model under control.

Thanks Dave,
Your absolutely correct, I must have made the Sub Groups while I was editing the upper and lower floors. I have seen the Explode option, but did not know what it did. Seeing the word Explode did not sound like a good thing lol.

That is a great way to think of Groups & Components. Hopefully I can keep this house model a little more under control than my last one.

Explode is taking the sandwich out of the bag and throwing the bag away. If you want to add cheese or mustard to your sandwich and put it back, it makes more sense to just open the bag, make the addition and then close the bag up again. sometimes though, exploding is a good thing.

It’s a really bad thing when someone mistakes it for a command to create an exploded view of a model and then use it on all of the groups and components in the model.

Good luck.