PEX, a flexible tubing that comes in long rolls, offers several advantages over traditional piping. First, you can usually make long continuous runs, eliminating most elbows and joints. You can snake long runs through joists and studs. Second, PEX doesn't sweat under high humidity conditions, and it's also resistant to bursting, even if the lines freeze solid. Third, joints are easier. You add fittings simply by crimping metal rings over barbed fittings using a special crimping tool.