Is underlay necessary for panels?
The underlay for panels is an indispensable and essential element that performs several very important functions. It provides proper thermal insulation—the thermal resistance parameter is especially important when installing underlay over water-based underfloor heating. Selected underlays can effectively protect against moisture damage and reduce noise. Additionally, the underlay protects panels from deformation and helps level the floor or subfloor. When properly chosen, it can also serve as soundproofing in rooms, eliminating unwanted footstep noises. The underlay layer perfectly fills the space between the hard subfloor and the panels, minimizing the risk of deformation to almost zero. It also stabilizes floating floors, such as vinyl panels installed with a click system. Therefore, using underlay also prolongs the lifespan of the panels, which is important to remember. It’s worth noting that manufacturers always require using underlays of appropriate density, thickness, etc., in their installation and usage guidelines. Skipping the underlay can lead to panel damage, and the manufacturer may refuse warranty claims in such cases.
Which underlay for vinyl panels?
The market offers a wide range of recommended underlays for vinyl panels, as these floors are very popular thanks to their features including water resistance. Choosing an underlay with the best technical parameters must always be supported by the certainty that it is designed specifically for rigid vinyl flooring (often called Rigid or SPC). What should you mainly pay attention to? Resistance to dynamic loads (DL) is crucial, which results from compressing the underlay under load. It’s best to choose underlays with a minimum density/weight of about 1000 kg/m³. A durable and thick underlay should also provide good sound insulation, around 20 dB. While it’s impossible to completely eliminate unwanted noises, selecting the right underlay can significantly reduce them. Underlays are also tested for compression resistance, often described by the CS symbol. A good underlay for vinyl panels should have a minimum CS value of 200 kPa. For use in public buildings (e.g., schools, hotels), fire resistance rating BFL S1 is important—this is a very good result. Therefore, before purchasing underlay, make sure to check the parameters listed on the label attached to each roll of flooring underlay. Also remember to prepare the subfloor properly before installing vinyl flooring—it must be stable, dry, and level. Due to their thickness, vinyl floors require very well-prepared subfloors in terms of evenness.
Types of underlays for panels
There are several types of underlays for flooring panels, mainly differing in the materials they are made from, which directly affects their durability and properties. The best choice tends to be underlays made from polyurethane-mineral mass, which are exceptionally durable and, importantly, consist of over 90% natural products. Such underlays should be between 1.4 and 1.6 mm thick and have an appropriate density of about 1000 kg/m³. Keep this in mind, as it is very important, and almost always vinyl/LVT floor manufacturers specify requirements regarding the underlay used. This type of product is excellent for rooms subjected to intensive use. There are also underlays made from extruded polystyrene or polyethylene, but always verify their density.
Users with underfloor heating installed under vinyl panels should choose underlays no thicker than 1.4 mm and resistant to temperature changes. The lower the thermal resistance index, the better. The best underlays are made of polyurethane with mineral additives, having a thermal resistance of R-0.009 m²K/W.
The underlay for vinyl panels should not only be durable and made of high-quality materials suitable for this type of flooring but also have the appropriate thickness. Most commonly, vinyl panel underlays are 1.4 mm thick. A properly selected underlay is also necessary when installing vinyl floors over existing ceramic tiles – in this case, underlay must be used as well.
