Levelling your base floor: hard or soft underlay?

A good underlay can make the difference between a bumpy surface and a perfectly smooth floor. But there’s a major difference between hard and soft underlays.

Hard or soft underlay

Hard underlays

Irregulariteit of less than 2 mm can be levelled easily using an appropriate underlay. However, it is always important, to determine the nature of these imperfections. Bridging grooves from an existing tile floor, for instance, requires a hard underlay of at least 5 mm in thickness.

Soft underlays

Small imperfections—like sand, concrete grid or glue residue—confined to limited areas in your base floor, call for a softer underlay. The soft material will easily incorporate these tiny bumps and holes and create a smooth flooring surface.


Levelling compound

When irregularities exceed 2 mm, applying first a layer of levelling compound—on the afflicted area, or on the entire surface—to smoothen your base floor is recommended. Afterwards, a soft underlay finishes the job and creates a solid base for your flooring.

Underlay Advisor

Find the perfect underlay in a few clicks with our 'Underlay Advisor' .