I know that the required deck size is 60 cards, and that you must have 7 Plot cards and a House card.

So, do the Plot cards count towards the required 60? Does the House card count towards the required 60?

60 cards is the limit of your draw deck. The plot deck and the House card are separate from your draw deck (and so are agendas, which are not even considered to be in play).

Thank you.

I figured it worked like this, but I wasn't sure.