I'm going to knock on my ceiling/my neighbor's floor.
But why are you going to do it?
Because they make a lot of noise upstairs.
You shouldn't knock on your ceiling. If your neighbor is making noise then you should knock on their door to ask them to stop.
That does sound a lot faster, thank you.
Yeah, it's rude to knock on the floor. You don't want them knocking on your ceiling, right?