Sounds transmitting between floors is a common problem. Music, TV, conversation, and other noises can easily carry down to the floor below. Likewise, sounds from below can drift through ceilings to rooms above. Various elements within a space such as the flooring, walls, and furniture have the ability to either mute or amplify noise.
It may be far-fetched to completely soundproof a room, but there are, however a few things you can do to tone down the noise pollution between your spaces.
Insulation Between Floors
The best wat to truly block sound is separate surfaces. Any kind of continuous material acts as a type of acoustic bridge that effortlessly moves vibrations from one space to the next.
Structurally separating surfaces is a very expensive solution that is usually reserved for spaces like home recording studios or high-end home theaters. Placing a dense sound barrier in the open joist spaces between the floors is the most effective way to separate the surfaces enough to slow the transmission of noise.
This is done is by removing the ceiling drywall and filling the joist space with fiberglass or rockwool insulation. This method does require working around obstacles, like electrical wires and recessed lights that extend into the ceiling.
For added sound insulation, the drywall can be rehung on resilient metal channels that allow the drywall move slightly which can help deaden vibrations. Adding a second layer of drywall if applicable makes this type of barrier even more effective by adding mass to the ceiling.
Generally, flooring underlayment is installed on top of the subfloor with the goal of providing a smooth, even, and predictable surface for a new flooring installation.
Closed-cell foam underlayment is an easily obtainable option that comes under many different brand names. While not the most effective, polyethylene foam underlayment is an easy way to absorb some sound.
Beyond the straightforward foam underlayment marketed for laminate flooring is another, more expensive type that is often called acoustic foam. Regardless of their physical properties, soft flooring underlayments will often claim that they are effective against blocking sound. While this is certainly true to an extent, it is important to point out the different between these types of underlayment and others that claim to be acoustic underlayments.
Acoustic underlayments are very dense materials designed to absorb sound vibrations. One easy way to determine foam density is to look at its weight in relation to its size.
Recycled felt underlayment is an eco-friendly, effective method for noise reduction. Although it tends to run about twice as expensive as polyethylene foam, felt underlayment is a good choice for sound absorption if your budget can handle the additional cost.
Recycled felt underlayment is about four times heavier than foam and thus much denser. This is your best bet for soundproofing engineered wood or laminate flooring.
Plywood underlayment is most often used under thin, flexible flooring materials like vinyl or linoleum tiles, but is only moderately effective as a sound blocker. Red rosin paper or tar paper, which have no sound-blocking advantages, are sometimes laid on top of the plywood to minimize squeaking.
You can do better than plywood underlayment by installing specialized acoustical underlayment on the subfloor. Acoustic underlayment systems differ from the straight plywood option because the systems elevate the flooring on sleeper boards. This elevation creates a dead air zone that significantly reduces the transmission of vibrations from one floor to the next.
Cement boards are used as a base for tiling. They can be a slightly better sound-blocker than wood because of its density.
Whether for new construction, an existing build, or even an apartment unit, there are methods and products that can make your hardwood or laminate flooring not only look great but also sound fantastic.