Take the ‘opportunity of silence’

One type of stone-wool insulation is this Canadian-made Roxul STEVE MAXWELL/OTTAWA CITIZEN/POSTMEDIA NETWORK

If you’re planning a renovation this winter, then don’t pass up the opportunity to make your home a little quieter.

The ‘opportunity of silence’ refers to the fact most renovations involve the total gutting of the room needing attention.

Gutting a bathroom or kitchen means removing not only the existing cabinetry, but the flooring, light fixtures, and the drywall, thereby exposing the studs— essentially bringing the room back to its original state of framing.

Gutting a room becomes necessary when basically every component in the room is being replaced.

Replacing fixtures often results in having to re-direct the electrical wiring and plumbing pipes, or updating them to today’s codes and standards.

The error homeowners make, is after all the electrical and mechanical changes have been made, the wall simply gets closed up again with drywall in preparation for the cabinetry. That’s what’s referred to as a missed opportunity of silence.

The thing about rooms, especially kitchens and bathrooms, is they create noise, noises that in most cases need not be leaked or transmitted into neighbouring rooms. So, if you were lucky enough to score tickets to the Habs game, yet unlucky in your choice of the burrito special at Senor Rodriguez’s take out Tacos, the continued tooting of your horn after arriving home need not be advertised any further than your washroom.

How to make a wall increasingly more sound proof means first understanding a few terms.

A wall assembly will have a STC (sound transmission class) rating, based on how effectively the wall prevents sound from moving from one room to the next. So, the higher the STC rating, the better that wall will be at blocking sound.

Decibels (db) are simply a measurement of how loud something is, based on a sound pressure scale. For example, a casual conversation will register at 40 db, a large truck driving by at 80 db, and your home’s fire alarm at 100 db.

Frequency is measured in hertz (Hz), and relates to the tone, or time cycle of a sound. So, the low sound created by a tuba would register 30 Hz, whereby the clashing of two cymbals might register 10,000 Hz. Humans can only hear sounds that occur between 20 Hz and 20,000 Hz, with the capability of registering and effectively translating sound frequencies, and range of frequency, declining with age.

This might explain why after 25 years of marriage, men can still effectively receive and translate the low frequency sounds being emitted from the television, yet have difficulty registering the higher-pitched sound of their wife’s voice when asking them to take out the garbage.

With the wall cavity opened up, now’s the time to make your soon-to-be renovated bedroom, bathroom, or kitchen, a little more sound proof.

A standard 2×4 wall with half-inch drywall on both sides has a STC rating of about 30. If casual conversation creates about 40 db, a standard wall assembly will somewhat muffle the room-to-room sounds of regular conversation passing through, but will do little to impede the decibel frequencies created by any loud music or television sounds.

Muffling this noise transmission, or creating a transmission loss, will mean having to slightly modify and beef up our regular wall assembly with a number of sound-absorbing products.

The easiest modification one can make to a wall assembly is the addition of Roxul Safe n’ Sound insulation. At 3.5 inches thick, the Safe n’ Sound batts conveniently fit into any 2×4 or 2×6 wall, and bump up the STC rating by 10 to 12 points. Now you’ve got a wall assembly that’ll at least muffle out most regular low sounds.

Bonus to the Safe n’ Sound’s ability to block sound, is its ability to limit the spread of flames, somewhat creating a safe room, at least for a few key minutes.

So we’ve managed to block the sound of casual conversation, now what about the clash of cymbals? That’ll be next week.

Good building.

As published by the Standard-Freeholder
Handyman's Hints Standard-Freeholder Cornwall Ontario by Chris Emard

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