Acoustic Underlays Beneath Laminate Flooring
Placing acoustic underlay underneath laminate flooring greatly enhances your living comfort, as it noticeably reduces reflected walking noise within your home. If you live in an upstairs flat, your neighbours below will also appreciate not hearing every step you take through the ceiling (transmitted impact sound). For these reasons alone, acoustic insulation is a very important addition. But that’s not all – it delivers other benefits as well:
- Extra thermal insulation
- Compensation for unevenness in the floor
Putting down acoustic underlay when installing new laminate flooring requires only slightly more work, but yields enormous advantages. This definitely makes it a worthwhile investment.
Kinds of Acoustic Underlay
A large range of acoustic underlays is available. Which one you should choose depends on your requirements and, of course, your budget. There are underlays made of different materials, and they come in a wide variety of formats and thicknesses. For example, you can select one of four different SWISS KRONO acoustic underlays to meet your expectations and needs:
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SWISS KRONO
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SWISS KRONO
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SWISS KRONO
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SWISS KRONO
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| Material |
Foam
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Foam core with PE lamination
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PU core with aluminium foil lamination
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PU core with aluminium foil lamination
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| Thickness |
2mm
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2mm
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1.8mm
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2.8mm
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| Attenuation of transmitted impact sound |
***
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*****
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****
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****
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Noise reduction
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**
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**
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****
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****
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Resistance to compression
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*
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*
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****
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***
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Heat transfer coefficient (u-value)
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0.042 m²K/W
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0.063 m²K/W
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0.01 m²K/W
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0.01 m²K/W
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Supplied as
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Rolls
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Rolls
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Rolls
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Rolls
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Recommended laminate thickness
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Up to 12mm | Up to 10mm | Up to 12mm | Up to 12mm |
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Special features
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- Fast installation from the roll |
- No additional vapour barrier required (2-in-1 product) |
- No additional vapour barrier required (2-in-1 product) |
- Highly effective insulation
- No additional vapour barrier required (2-in-1 product) |
All SWISS KRONO acoustic underlays also compensate for minor unevenness in the substrate. Somewhat thicker products like 2.8mm-thick SWISS KRONO Superior Sound are of course able to compensate for somewhat greater discrepancies than thinner ones like SWISS KRONO Basic, which has a thickness of 2mm. However, acoustic insulation is not the best choice for dealing with extremely irregular subfloors. It reaches its limit at about 3mm of unevenness per metre of floor. If the differences in height are larger, other steps will need to be taken beforehand.
You should also keep in mind that carpeting is not a good substitute for acoustic insulation. If the floor is covered by a carpet, you should remove it first before laying the laminate.
Installing Acoustic Underlays
Install sheets or boards of underlay at right angles to the laminate flooring panels. This is the best way to prevent lengthwise joints in the underlay and laminate from coinciding.
Unlike laminate panels, there is no need to leave a gap between the underlay and walls. If the underlay product you choose has an integrated vapour barrier, it should actually extend up onto the wall by about 3cm. Unroll sheets of underlay side by side so they touch one another and join adjacent ones with sticky tape. SWISS KRONO Basic Plus includes an overlapping flap with integrated sticky tape to facilitate installation.
With SWISS KRONO Premium Sound and Superior Sound, apply sticky tape underneath to connect adjacent lengths. Most other products let you simply attach sticky tape from above to join and stabilise adjacent lengths. There is no need to glue boards together; it is enough to simply place them closely together. To make sure that they don’t slip out of place, however, you can also resort to sticky tape. Use a good-quality, sharp Stanley knife or box cutter to cut sections of acoustic underlay to size.
#underlayment
Various underlayment materials are available for meeting different requirements. On mineral substrates, it’s essential to spread a vapour barrier before installing underlayments to insulate against impact sound and reflected walking noise. This is the basis for laying the actual laminate flooring using the “cut-and-clic” method.
Installing Acoustic Underlay on Underfloor Heating
If you have underfloor heating, make sure that the laminate flooring and acoustic underlay have adequate thermal conductivity. Together they should not have a u-value of more than 0.15m² K/W or you will have to turn up the heat to stay warm. It must also be possible to steplessly adjust the underfloor heating to easily prevent too much heat from passing through the underlay too fast. The maximum possible laminate thickness is indicated on all SWISS KRONO acoustic underlay products.