How to soundproof floors

If you are considering soundproofing your floor it is important to think about what you want to achieve. Do you want to stop nuisance airborne noises coming up from the property below or are you trying to reduce footfall impact noises from your property to the neighbours below?

What type of noise are you been affected by?

What’s your situation? Are you living in an apartment or flat and being affected by noise from neighbouring properties above or below? Or are you living in a self-contained property, such as a detached house, where you want to reduce the noise from other rooms, such as a games room or cinema room or to make a bedroom quieter for sleeping?

If you live in a connected property like an apartment, clearly you will only be able to treat the floors that you have access to. So, if your noise problem is coming from a flat below, then you can treat your floor easily. If it is from above, obviously you won’t be able to soundproof the floor in someone else’s property, but you could be able to take action by soundproof your ceiling

Figuring out what type of noise you want to reduce

There are two main types of sound transmission that we need to consider when soundproofing – airborne sound and impact sound. The different types of sound insulation products available will target either of these, with some products also addressing both.

Sound insulation designed to tackle airborne sound transmission will add mass to make it more difficult for soundwaves to get through the dense material. Products like the Hush-Slab 100 sound absorber panels are one such product, made from mineral wool fibres in a dense but flexible slab which is very effective at disrupting sound transmission paths.

For impact sounds, the insulation needed will generally be to add a resilient layer. This is designed to provide separation between materials, such as between a timber joist and a floorboard, to break the sound transmission paths. There are numerous products of this type available, such as rubber based membranes and joist strips, so there is a solution for almost all types of floor construction.

To reduce impact noises (e.g. footsteps) being transmitted down to the property below we recommend installing acoustic floating flooring or overlay acoustic matting. These are easy to install and you can lay the boards directly over joists or as an overlay over timber or concrete floor structures (when correctly specified).

The things that will determine what floor product is to be used

1) the performance levels you are looking to achieve and
2) what the final floor finish is going to be and how it will be laid over the top of the chosen acoustic floor system.

For example, Hush Mat 15 can be installed directly under carpet or engineered timber floors.

Solid timber flooring will need to be installed over a timber faced acoustic overlay board and a tiled floor finish can be laid over a timber or cement particle acoustic flooring.

The best way to treat airborne noise is to treat the ceiling of the property below.

This is not always possible depending on how willing the neighbour is to help stop the problem.

A correct ceiling detail will be the most effective but if you are only able to treat the floor from above the structure (your floor) you need to look at adding a degree of absorption within the construction and some high mass acoustic floor products.

Hush Slab 100 placed between the joists and a high mass flooring such as Hush CEM Panel 28 or Hush Mat 15 will be needed.

What type of floor do you have?

The construction of the floors in our homes generally falls into two categories – timber construction using joists and boards or concrete with or without a screed.

The two different types of floor construction require very different soundproofing methods. For example, timber floors will generally feature voids between the joists which can be infilled using sound absorber slabs to address airborne noise, whereas concrete floors will not. They will, however, have a greater sold depth which may mean they only need to be treated for impact noise using a rubber membrane.

What is flanking sound and how to reduce it?

Sound will always try to find a transmission path, whether that is through solid materials, air or around soundproofing measures. That is why any attempt to soundproof a floor must address what is known as ‘flanking’, where sound waves find gaps in the insulation and undermine its performance.

This is achieved using different types of seals for the perimeters of floors, such as Hush-Seal 20.

Cost and the loss of room space are other important factors that you should think about. Today’s advanced soundproofing products from Hush Acoustics are extremely effective when they are used in the correct ways, but if your problem is severe, achieving the highest performance may be costly.

A lower specification solution will be less costly, but there will be a trade-off in that it will not provide the very best level of soundproofing – it is a cost versus performance dilemma.

Adding insulation to a floor is likely to add depth too, and this will have an impact on the rest of the room. The floor to ceiling height will be reduced, perhaps only slightly, and once the soundproofing is completed, redecoration and new floorcoverings are likely to be required. All of which will need budgeting for.

Best soundproofing products for timber floors

One of the most common ways to soundproof a floor constructed using wooden floorboards and joists is to add a floating floor or replace the floorboards with acoustic floor panels. Both can be achieved using products such as Hush-Panel 28. This is manufactured using a high quality, moisture-resistant chipboard bonded to a resilient felt layer – Hush-Felt – adding density and separation in one. Once laid, the panels are sealed around the perimeter using one of the various seals available from Hush.

As we have mentioned already, the floating floor can be supplemented with joist strips to separate the floorboards from the joists – adding another resilient layer – and Hush-Slab 100 sound absorbers used to infill between the joists.

An acoustic underlay can also be used under your floorcovering, such as Hush FFR Resilient Underlay, to reduce impact sound transmission.

Soundproofing for concrete and screed floors

If you have a concrete floor, impact noise such as footsteps can be treated using rubber membranes. These will generally be required to provide separation between the floor surface and the structure.

Hush Acoustics offers a range of rubber-based products which we cover in more detail in this sound insulating screed floors guide. Applied in the right way, these soundproofing products can make a significant difference.