Noisy neighbors and hard surface flooring don't mix.
You can, however, reduce noise transference by using 'sound absorbing underlay' for floating hardwood or laminate floors.
Here are some general points about sound-absorbing underlays that may help you with your choice:
Make sure that the underlay you choose has been tested using ASTM International (formerly American Society for Testing and Materials) standards . Ask for paperwork that substantiates the underlay manufacturer's claims of the product's sound absorbing qualities. The product should have been tested in accordance with ASTM E-492.
The test results should show a couple of things....
1. An IIC (impact insulation class) rating
This is the number used to rate the sound absorbing characteristics of an acoustical barrier when noise is produced by two bodies striking one another. Eg: foot steps, moving furniture, objects falling on the flooring surface. The higher the rating in this test the better the product is at absorbing sound. Most products on the market have an IIC rating of between 60 and 75.
2. An STC (sound transmission class) rating
This measures a building material's (in this case underlay) ability to absorb audible noise such as voices or TV sound. Most products on the market have an STC rating in the high 60's.
IIC and STC ratings increase when the mass of the flooring structure increases ( eg. increasing concrete slab thickness or adding an additional layer of gypsum board to the ceiling surface below) or when the floor structures component members are "isolated" from one another so that it is not a continuous assembly. Drop ceilings also work to reduce sound transference.
90% of the noise problems in condos exist because of lifestyle. If you have a noisy lifestyle, then your neighbors will hear you. There is not a sound absorbing underlay on the market that is going to stop every clack and bang, or noise from a loud TV from transferring through walls or floors to neighboring
suites. Yes, an acoustical underlay with a good IIC and STC rating will reduce the noise transference but it will not eliminate it.
With this in mind, strata councils or building managers put rules in place (by-laws) that require a high IIC rated underlay be used for any new wood or laminate floor installations. By doing this, they can say they
made a reasonable effort to keep noise transmissions to a minimum should there be a complaint.
In some cases, just to keep the peace between neighbors, by-laws go further and demand, for example, that 60% of the new hard surface flooring area be covered with area rugs. If you've ever lived beneath noisy people who have hardwood flooring you will understand why.
1. Check your building's by-laws regarding sound barrier and IIC / STC requirements for hard surface flooring before installing your new floor. In this case, it's better to ask permission than beg forgiveness!
2. Set expectations - living creates noise! If you have a couple of active kids, play the piano, wear shoes
that clack on the floor as you walk around the apartment, walk with heavy foot falls, drop things, have your stereo or TV sound turned up louder than most - then you are going to be heard by your neighbors.
3. Use area rugs to help reduce noise.
4. Do not nail wood flooring to an acoustical underlay. This allows for too much movement (deflection) in the wood floor pieces and will likely lead to squeaks and gaps. Also, nails or staples facilitate sound transference similar to that of a tuning fork. If you are installing your flooring over a wooden sub-floor and want to insulate against sound transmission, then you will need an altogether different kind of sound barrier system- if this is the case then explore your options through an architect or experienced builder.
Note that if your subfloor is wooden and does not have an acoustical concrete topping live in a wood frame building with no acoustical concrete topping between floors, a sound absorbing underlay with the highest IIC rating, will not stop sound transference. Most underlays achieve their IIC and STC ratings from testing over concrete sub-floors. Wood frame construction and plywood substrates are notoriously bad at muffling sound.
Hi-rise concrete buildings are best for natural noise containment because concrete is a great sound barrier. Most hi-rise construction consists of 6" to 8" of concrete sub-floor between you and your neighbors below.