The underlay is an absolutely essential part of your new laminate floor. Here are the most important reasons for this:
The right underlay ensures that your laminate flooring will look absolutely perfect: the levelling effect will smooth out all minor irregularities, making perfection the standard for your new floor.
Additionally, your underlay has an important function with regard to thermal insulation: if the various floors in the building you live in are maintained at different temperatures (e.g. a living room above a garage) the correct underlay will serve as a buffer.
Underlay also provides acoustic insulation. It dampens not only the noise you make when walking on your laminate flooring (reflection sound), but also that of someone else walking on the floor above you (transit sound).
In conclusion, it is important to know that good underlay offers protection against rising damp thanks to the DPM or damp-proof membrane. Indispensable!