When choosing an underlayment for your hardwood or laminate floor, be certain that you know what is acceptable as recommended by the flooring product manufacturer. This will prevent voiding the manufacturers’ warranty by ensuring that you will not select unapproved materials. The most commonly used hardwood and laminate underlayment materials are: 

● Standard Foam
Standard foam is the most commonly used underlayment material for hardwood and laminate flooring. It is actually thin piece of foam which is placed on the top of a plywood or concrete sub-floor. A standard foam underlayment is the best choice for use in lower humidity areas where moisture is not expected to be a problem. For areas that are high in moisture, like Florida for example, standard foam is not the correct choice, unless you want to install it with an additional moisture barrier. 
● Combination or Combo
As its name implies, combo is created by combining film with combustion foam. This underlayment is an excellent choice for new flooring in a remodeling project that has to take into account any moisture rising from the sub-floor below it. This material can be applied on top of concrete or plywood. A combo underlayment is merely a foam underlayment with a sheet of moisture barrier that has already been attached. 
● Upgraded
As its name suggests, an upgraded underlayment material for wood or laminate is merely dependable foam which has been created from tough materials like rubber and fibers. An upgraded underlayment is popular for remodeling projects that need an ample quantity of noise reduction between rooms. An upgraded underlayment does not reduce the sound of foot traffic walking on the hard surface, a typical misconception about this product. 
● Cork
Cork is a costly choice for an underlayment, but it is also preferred if the homeowner desires an extremely significant amount of noise reduction between two floors. Cork will not deliver increased comfort for people walking on hardwood or laminate surfaces, and will not lower the noise resulting from foot traffic on the room’s floor. Cork may also be utilized to elevate the level of the sub-floor to make certain that all the floors in a home’s level are the same height.