Exclude channels from being recorded?

That sounds like the definition of a shielded sub...

but do I have to record it as a sub before I exclude it?

You put your houselights on a sub, I guess you already have that. In the sub's properties go to priorities and choose Shielded.

Channels in a Shielded sub can only be controlled by this sub but they cannot be controlled manually nor can those channels live outside the sub (i.e. not in cues).

Ok awesome thank you so much!

In your Fader Config tab, you can click on your submaster that houses your houselights and select 'Exclude: Record' option.

This excludes the content of that submaster from being recorded.

(You can also access the same parameter from the "Submasters" tab.)