Did you ever hear your kids in the basement playing and wondered what you could do to drown out the noise?  One of the things that you can do is install floor sound insulating.  This type of insulation allows for noises such as loud TV and stereo systems, children playing or talking loudly, vacuum cleaners, washer, and dryer noises to be lessened dramatically.
Even though it is not a necessity, a lot of people today are installing floor insulation.  Preferably, the best time to install it would be during the construction phase of the home as the floors have not been laid yet. It should be laid at the same time that the walls and ceilings get insulated.   The common insulation used during the process of insulating the exterior walls, ceilings, and the attic is fiberglass insulation.  However, this might not be a great choice for your floors.   For floors, you have the option of installing corking or rubber based floor insulations.
When insulation is installed during construction they place materials between the flooring layers.  The way floors are built, there are joists between the supports and then a plywood base and then additional sub-flooring to place the final floor on.  It is in this area under the additional sub flooring that other insulation materials can be added to increase the sound proofing of your home.  This is why it is easier to install it during the construction phase of a home.
So if you live in a home that is already finished, is it too late to install insulation in the floors?  It is never too late.  If you are doing some superficial repairs such as putting in new carpet or having new flooring installed, that would be a good time to consider adding floor insulation.  This will dramatically decrease the noise level in any existing home.
The way this is done is when the old floor coverings has been removed, new floor insulation can be added to the top of the sub-flooring. In other words, if you were having new vinyl floors put in your kitchen, before they put in the vinyl floor, they would put the insulation down on top of the sub floor and then put down the new vinyl flooring.  It does not matter what type of flooring going on top.  What is more important is the type of insulation you use for the soundproofing.
The best insulation for walls and ceiling is the fluffy fiberglass that that the paper backing and is pink or yellow in color. However, for the floors it is a different story.  A rubber or cork insulation is the best most durable way to go.  It also has the added feature of being able to go down efficiently and not cause the new floor to rise up.
You may ask why go through all this trouble. Well, here is why; as a house gets older the creaks and noises seem to increase, just like everything else as it gets older.  So to keep noise from seeping from the rooms above adding floor insulation will make a big difference.  As this is generally a pretty easy project for the average do-it-yourselfer, there is no reason why one should not attempt to do this if they are already renovating the flooring in an existing home.  This will also help with those irritating squeaky floors that have had their screws come loose over the years.