The purpose of the underlayment is to provide a smooth, flat surface, reducing subfloor imperfections. Unlike solid wood floors, laminate floors are very thin and are applied floating without being glued or nailed anywhere.

The underlayment is necessarily applied under the laminate floor and offers:

• Smoothing small imperfections of the receiving floor.
• Floor stability.
• Thermal insulation (depending on its category).
• Sound insulation (depending on its category).
• Acts as a vapor barrier.
• Makes walking easier.

Without underlayment, the space will have an echo, the floor will not be stable enough, and noise will be transmitted more easily. Its properties remain stable over time, it does not promote the growth of fungi and bacteria, and it does not irritate the respiratory system.