A metal roof is no (noisier) than a traditional roof. When you have a metal roof, you’re going on top of a solid deck. In that solid deck you have an attic space, insulation, a ceiling. Metal roofs are usually installed with solid sheathing attached to the underlayment, which helps reduce noise. If you don’t hear rain today, you won’t hear rain with a metal roof on. In fact, a properly installed metal roof will disperse rain to reduce noise.