Yes, you'd need to split a single signal for all of the connections in the house. But you're going to have to do that no matter what -- at the end of the line, there's only one piece of cable coming in from the cable company. It's just a question of whether you split it where it comes in from the street, and pull multiple runs to your enclosure, or you pull one run to your enclosure and split it all in there. You can do it either way, but when I have a choice I'm inclined to split it at the structured wiring enclosure (so just one run from the street). It's nicer to keep the majority of your splitters and connectors inside, out of the elements. And if you need to amplify, you can have your amplifier inside the enclosure, with an unsplit signal from the street as its input.