Underlayment is a critical component of a successful laminate flooring installation. It is a soft pad that is installed under laminate flooring to help the planks lay smoother, connect better, and feel slightly softer underfoot. Underlayment does two things that are critical to a successful laminate flooring installation: it takes out any minor deviations in the subfloor and delivers superior acoustical performance. Underlayment also provides adequate support for laminate flooring by absorbing sound, protecting it from moisture, and offering the best thermal insulation.

The type of underlayment chosen should be based on the environment, the type of floor chosen, and personal needs for space. The normal choice is a thin foam pad material made of polyethylene or polypropylene, which rolls out in sheets. Some laminate flooring planks come with the underlayment attached to each plank, while others require separate underlayment rolls.

The underlayment should be installed on a level and smooth subfloor to get an even finish on the laminate flooring. If the subfloor is plywood, a breathable foam-type underlayment is generally used. In most cases, a vapor-barrier-type underlayment should not be used when installing laminates on a standard plywood subfloor because wood is a natural material that needs to breathe. However, a moisture barrier underlayment is a good idea when laminate flooring is being installed in a high moisture area, such as a bathroom or basement.

In summary, underlayment is a necessary component of a successful laminate flooring installation. It helps to correct minor subfloor imperfections, provides superior acoustical performance, and protects the laminate flooring from moisture and wear and tear. The type of underlayment chosen should be based on the environment, the type of floor chosen, and personal needs for space.