Q. I’m doing a gut renovation. While I’m at it, how do I soundproof the walls, floors and ceilings?
A. Soundproofing is very, very tough. Tough enough that for the purposes of answering your question, we’re going to refer to “sound isolation,” which is the process of reducing, by some degree, sound transfer from one place or structure or material to another. “Soundproofing,” meanwhile, implies a complete elimination of unwanted sound and can be very difficult to achieve in most residential renovations or upgrades. It’s important to keep your expectations realistic.
A quick background on sound transfer
Sound energy can move through air—and even the tiniest amount of air can travel in any space—as well as through solids. But it moves through these mediums at different speeds and to different degrees.
Thus, you might stop sound from moving through a crack in a door, but the energy might go through the “solid” doorframe. Sound is also made up of a range of frequencies, from the “lows” to the “highs,” and different methods and materials are sometimes appropriate for higher- and lower-pitched sound.
Cut down on building noise
The first thing you’ll want to consider is just how much noise you’re dealing with and where it’s coming from. Do you want to reduce the sound from a playground across the street? Or do you live directly above a salsa club that’s open ’til 3 a.m.? These two problems require drastically different approaches.
If it’s the salsa club, we’d expect much lower frequencies and a much louder source (the club’s amplified sound system).
The most basic sound isolation improvement will be adding layers of materials. If you’re redoing the walls (which you will be with a gut reno), add a few extra layers of drywall. If you’re taking floors back to the joists, add two or three layers of plywood as a base floor, instead of just one, and then the finished flooring on top.
Read the full post in our Brick Underground column: ‘NYC Renovation Questions’ – where you get the unvarnished answers to your renovation conundrums.