Is it against regulations to have a neutral at a switch in a connector in a new build house?

Your question isn't clear to me. How is your switch wired? You can run a feed to the switch, and then a cable to the load. The neutrals are spliced in the switch box, and the hots connected to the switch terminals. Or you can run the feed to the load and a switch loop back to the switch. It that case, the white carries the current.