• Using LVT As Part Of An Acoustic Floor Solution

Using LVT As Part Of An Acoustic Floor Solution

CFJ (Contract Flooring Journal), the UK flooring industry's trade publication of choice recently published the following supplement written by iKoustic’s Director Rick Parsons which looks at Luxury Vinyl Tile) and LVP (Luxury Vinyl Plank) covering common questions about the floor covering, the steps that can be taken to ensure it is supported acoustically and more.

CFJ is widely recognised as giving the most authoritative coverage of all sectors of the flooring industry and we are thrilled that they published the below article.

Continue reading below for the full piece:

LVT (Luxury Vinyl Tile) and LVP (Luxury Vinyl Plank) are quickly becoming a leading choice of floor covering for both domestic and commercial settings. It is a low-maintenance, water-resistant, cost-effective, durable and aesthetically pleasing final floor finish. With an infinite number of designs available to choose from, it is easy to see why so many people are choosing this particular final floor finish.

The product build-up essentially consists of a thin laminate of a photographic layer sealed between a base and a clear top wear-layer. It relies upon quality digital pictures of actual samples, often of such material as wood or stone for its appearance. You can then get the precise look you’re after, regardless of the availability of the specific stone or species of wood and at a fraction of the cost.

As fabulous as the material is, there are often questions raised regarding its acoustic performance, “How noisy is LVT?”  This is clearly a very important consideration before leaping into the acoustic unknown. Whilst it will vary slightly between manufacturers, the acoustic properties of LVT itself are generally low level. It is a slim, lightweight and semi-rigid material. Effectively, it relies upon the structure around it such as the adhesive, acoustic underlay or floor characteristics for most of its noise reduction. Whether it is between floors within your own detached property, or an element in a Part E compliant partition between two apartments in a high rise, the same principles apply, reduction of impact noise and resistance to the passage of airborne sound are the requirements. Unwanted noise causes stress to us and others around us and we could all do with less of that in our lives. The risk therefore, is that by not understanding the physics of what is happening, it is all too easy to make some bad choices whereby you could end up with a “Nuclear Noise Bomb” and lose some “Good-Will” with the neighbours in the process.

The short summary is, that whilst LVT itself may not be an acoustic level product, it can still work well as a component in an acoustic flooring system if planned and installed correctly. But what steps can be taken to ensure that LVT is well supported acoustically?

Let’s examine a few things that will help keep impact and airborne noise to a minimum, starting with some physics and how sound behaves through a floor

  1. The sound we experience as human beings, is simply energy in the form of vibration reaching our ears through the medium of air, stimulating some nerves and then being interpreted by our brain. This word interpretation is key. It introduces a personal element as we all hear and react to sound differently. Some people are very sensitive, whilst others don’t even hear it.
  2. Sound can vary in terms of amplitude (volume), frequency (pitch) and wavelength (m). The lower frequencies are harder to control in buildings. The wavelength is so long, that it passes straight through walls. That is why you can hear a bass thud outside a Nightclub so easily. A 50Hz Bass sub in a home cinema will have a wavelength of almost 7m. The wall thickness to deal with this well would need to be almost 2m thick!
  3. Sound needs a medium to travel through – Air, concrete, timber, LVT. Broadly speaking the denser the material, the faster and further it will travel through it. Remember Westerns where the robbers put their ear to the railway track? They could hear the train through the metal track way before they could hear it through the air.
  4. There are two broad categories of sound transmission – Airborne (e.g. Human Voices) and Structure-borne (e.g. Heel Impact on the floor). They behave differently due to the medium they are travelling through and so need different solutions.
  5. It will sound different inside a room (Source room) with LVT than it will in the space below (Receiver room). This is because inside the room absorbing materials improve the sound but between rooms sound insulation or isolation are the best solution to reduce transmission.
  6. Mass is good for reducing Airborne sound. You can imagine that its easier to be heard behind a curtain than a steel door? The door has more mass and therefore it’s harder to vibrate it. Similarly, a concrete slab / screed floor has more mass than a timber floor so it will reduce airborne transmission more effectively, but it also transmits impact sound more readily because of its density and structure. Tap a steel RSJ with a hammer and tap a piece of rubber and notice the difference.   
  7. Untreated Hollow spaces resonate. The space between the floor of a timber joist floor and the ceiling below will resonate if it is empty. Think of it as a drum and your feet are the drumsticks. The sound needs to be absorbed in this space with fibrous material such as a Dense Mineral Wool, fluffy lightweight thermal glass fibre simply doesn’t cut the mustard. Its like putting a pillow in a bass drum. I have never yet found a hollow timber joist floor that doesn’t improve acoustically with mineral wool.
  8. The level of noise reduction required, may be determined by building regulations or it might be specifically detailed by planning for your particular type of use, proximity to your neighbours, where you are based and the structure type.

Let me pull that together for you and summarise with some elements that will help to ensure that your LVT solution remains acoustically effective:

  1. Concrete subfloors need more resilient material under the LVT. It is too thin to spread any impact energy effectively and so passes the vibration straight through to the concrete below. This is then heard clearly by the folks below. Acoustic underlays can vary from 1mm up to 20mm. The right thickness will depend on the level of impact noise reduction required, how dense the material is and how thick / stiff the LVT is. 
  2. Wooden Subfloors need treating with mineral wool between the joists and more mass adding into the system. This can be done by adding high density Acoustic matting, visco elastic membranes or materials such as cementitious particle board.
  3. Isolation is invaluable – Float your floor if you can. This will significantly improve acoustic performance. Perimeter Flanking band is key here to ensure that the lateral vibration does not pass footfall onto your walls.
  4. Choosing the right adhesive is not just a sticking matter … it can help isolate too.
  5. Great preparation is key. Flat even surfaces are essential to start with. Uneven, gaps or poorly adhered patches can create noise with slaps or taps over time.
  6. LVT is relatively soft and can damage easily, so a firm rigid base underneath is key. But, make sure this rigid layer is sat on an acoustic resilient layer with a perimeter flanking band around it.

In short, by focusing on the LVT as simply one component supported by an acoustic floor system, there are a number of measures that can be implemented to ensure we can all get what we want and Create Quieter Spaces Together™

iKoustic® is a UK based acoustic product specialist that design, manufacture, and supply sound insulation solutions for buildings. Our products and systems are focused on reducing noise transfer through floors, walls and ceilings. 

Talk to iKoustic® for the very best advice, as early in the planning process as possible. Indeed, it may well be that we can save you investing in material that is not needed to achieve the level of sound insulation or reduction. It’s a totally free conversation to understand your specific goals and then to offer sound insulation material advice and guidance based on many years of experience.

To find out more about LVT and iKoustic, visit ikoustic.co.uk/ where you can send us a message via the chat function or call 01937 588226 and speak with Rick.