Why use a moisture barrier under laminate flooring?
The role of the polyethylene vapor barrier (PE) is to protect the panels from moisture. It prevents condensation under the panels, eliminating the risk of dampness. Even a small amount of moisture can cause deformations and unsightly “bubbles.” Without a vapor barrier, the flooring will suffer permanent damage, making its use essential. Moreover, the manufacturer's long-term warranty won’t apply unless the PE vapor barrier and/or appropriate underlay are used.
Which underlay and moisture barrier work best under laminate flooring?
The most important factor when deciding which moisture barrier to use under laminate panels is its thickness. It is recommended to use a barrier at least 0.2 mm thick and certified. When installing, make sure the strips overlap with a so-called overlap. On this prepared (and of course dry) surface, lay the underlay. A moisture barrier is essential, for example, when using underlays like PROFI PE underlay, which is made of polyethylene foam with good density and appropriate thickness — this underlay is 2 mm thick and offers good properties like density and sound insulation.
A convenient solution is to buy an underlay with an integrated moisture barrier, enabling faster installation without needing to buy separate components. Examples of underlays that do not require separate PE vapor barriers are IDEAL PROFI 2.0 underlay and MAX PROFI 3 in 1. The first features very high density and uses natural raw materials combined with polyurethane binders. It protects against moisture thanks to two layers controlling water evaporation. Its other parameters are nearly perfect (as its name suggests), including a thermal conductivity coefficient of 0.009, impact sound reduction, and compressive strength. The second, MAX PROFI 3 in 1 underlay, combines a high-density polyethylene foam underlay with a polyethylene foil layer 150 μm thick, featuring a 60 mm overlap and a 19 mm wide self-adhesive tape to facilitate installation.
Both underlays not only protect against moisture damage but also provide acoustic and thermal insulation, making them suitable for use with water-based underfloor heating systems. Additionally, they help level uneven floors, and due to their good deformation resistance, will serve for many years, increasing the durability of laminate flooring panels.
