Which Underlay Is Best?


A common question for people when they are buying a new laminate floor – which underlay is best? The answer is dependant on a few factors;

  • Is the subfloor perfectly smooth?
  • Does the subfloor get damp at times?
  • Does heat escape through the floor?
  • Is the new floor going upstairs and does it need sound proofing?
  • Will you be using underfloor heating?

At Wood Flooring Kent we offer a number of laminate flooring underlays and Quick-Step flooring underlays to suit any requirement. In this article we’ll talk about what their attributes mean and which is best for a few standard scenarios.

Common Attributes

All hard flooring underlays have a few common attributes;

  • Thickness – With a perfectly smooth subfloor such as concrete, the thickness of the underlay is usually of little consequence. If your subfloor is not completely smooth such as with wooden floor boards, you should consider using a thicker underlay. Do be wary to check the installation requirements of the your new flooring as they may specify a minimum or maximum underlay thickness, for instance most floors that are less than 10mm thick will not be suitable for use with a 5mm underlay.
  • TOG Rating – A standardised rating for heat insulation. The higher the TOG rating, the greater the heat insulation of the underlay. If you are fitting your new floor in a room that has issues with the heat escaping through the floor (such as areas with bare floor boards for a subfloor), you will want to use an underlay with a higher TOG rating such as the Quick-Step Thermolevel Underlay for Quick-Step and Xtra Step floors, or Supergold 5mm Underlay for other laminate floors. If you are using underfloor heating, you will want to utilise an underlay with a very low TOG rating to allow the heat to pass through the underlay and into the floor, such as the Quick-Step Silent Walk Underlay or Wood Plus Quick Therm Underlay.
  • Impact Noise Reduction – Measured in dB, the impact noise reduction tells us how much sound travelling down below the floor is reduced. When fitting a floor in an upstairs room you will typically want to use an underlay with a high INR rating.

Underlay For Quick-Step and Xtra Step Floors

Quick-Step and Xtra Step floors come with their own range of underlays which must be used with these floors, and only with these floors. There are 4 options in the range; Basic Plus 2mm Underlay, Unisound 2mm Underlay, Silent Walk 2mm Underlay, and Thermolevel 5mm Underlay.

Quick-Step underlays have an additional attribute – Sound Reflection Score. This is a score created by Quick-Step to measure how effective the underlay is at reducing the noise reflected back into the room when you walk on a Quick-Step or Xtra Step floor. Underlays are scored out of 4, with 2 being the lowest score and 4 the highest.

Dealing With Damp

If your subfloor has issues with damp coming through, it is always recommended to lay a Damp Proof Membrane prior to installing your new floor. For extra protection or just as a precaution, we advise also using an underlay with a vapour barrier.

Almost all of our underlays are equipped with a vapour barrier, with the exception of the 2mm Acoustic White Wood & Laminate Underlay and the 5mm XPS Foam Wood & Laminate Flooring Underlay, though the latter is constructed with moisture resistant material.