Acoustic floors for each type of finish -

Acoustic floors for each type of finish

Posts by Russell on November 18, 2020 in FAQ's

Choosing the right acoustic floor for the type of finish is key to getting the soundproofing method correct.

So type of floorboard, underlay and acoustic treatment should you use for carpet, vinyl and wood finishes?

Achieving the desired acoustic performance, whether for building regulations, planning conditions, Robust Detail compliance or just for preference, is the main focus of Hush Acoustics and all the products and systems we manufacture.

Acoustic performance is paramount but when selecting the correct acoustic flooring other things do come into account. The structure of the building, floor height build up and the floor finish that will be installed on the acoustic floor. The UK construction industry is seeing many issues with floor finishes and acoustic flooring working (or not working) in conjunction with one another and it is down to incorrect installation or specification of products including the chosen floor finish.

Our team have some general advice when choosing and installing floor finishes with sound acosutic products. This is purely guidance to help specify the correct Hush product for the development.

Hush are not held responsible for floor finishing issues and it is key that the design team and main and sub-contractors are in agreeance as to how all the elements are to be installed.

Carpet and underlay finish

Generally, rolled out carpet, with an underlay, has very little concern as a floor finish. Carpet and underlay can be installed over all Floor products and systems as long as its even and been installed correctly. Carpet can offer great sound reduction qualities as it’s a fabric and doesn’t have a hard exterior for sound to bounce off. The only consideration should be the type of underlay and overlay boards you use as you will need to take into account the sound created by walking on floor. You may also need to think about your joists and if the creak, this may need treatment too.

You can read about to stop creaking floors here:

Timber laminate or engineered timber floors

With most timber laminates or engineered timber floors there is little concern with the installation over the Hush Acoustic flooring product range.

Hush have a range of rubber underlay products such as the Hush FFR in 3, 5, 6, 8 and 10mm thicknesses, a cork/rubber underlay in 3 and 4.5mm thicknesses and a high performing underlay called Hush Mat that comes in 12 and 15mm thicknesses. All these products can be laid directly under a timber laminate or an engineered timber flooring.

The timber topped or cement particle topped acoustic flooring such as Hush Panel 17, Hush Panel 23, Hush Panel 28, Hush Panel 32, Hush Panel 33, Hush Panel 37, Hush Panel Premier, Cem Panel 28, Hush Cem Panel 32, Hush Ply 28 and Hush Ply 32 can all be installed under timber laminate or engineered timber flooring. We always recommend that an additional thin acoustic underlay is placed between the top of the acoustic flooring and the timber floor finish to remove the connection between the two hard surfaces.

The Hush Acoustic flooring product must be installed as per the manufacturer’s guidance.
For further information and any installation guidance requests please speak to the Hush Technical Team on 01519332026.

Solid timber plank flooring

Solid timber plank flooring needs to be bonded and secret nailed to a substate. This floor finish type does not have T&G joints that click together such as engineered timber flooring or laminate. The planks are placed together, bonded and mechanically fixed in place. Therefore, the timber topped or cement particle topped acoustic flooring products need to be used to isolate this type of floor finish. Hush Panel 17, Hush Panel 23, Hush Panel 28, Hush Panel 32, Hush Panel Premier, Cem Panel 28, Hush Cem Panel 32, Hush Panel 33, Hush Panel 37, Hush Ply 28 and Hush Ply 32 can all be installed under solid timber flooring.

The solid timber floor can be bonded, and secret nailed to the top of the acoustic flooring. The secret nailing must not penetrate through the top surface of the acoustic flooring product. As the floor finish must only be secret nailed to the top surface it is key to make sure the correct fixing is used. Also, picking the suitable acoustic flooring, with the correct depth of timber/cement particle board is also key. The timber floor finish supplier will be able to offer advice on the adhesive to use to bond the floor finish to the acoustic flooring. Some floor finish suppliers only like to work with plywood, hence Hush Ply 28 and Hush Ply 32. This needs to be checked prior to specification of the acoustic flooring.

Tiling (porcelain)

Hush acoustics has a dedicated section on the website to tiling over acoustic flooring. This can be found here

However, some brief installation points are as follows:

When tiling over an acoustic flooring it is imperative that an anti-fracture membrane is used within the flexible tile adhesive. Hush has tested its products with three of the leading anti-fracture membrane companies. These are Norcros, with their product Permalayer, Dural, with their product CI Matting and Schluter, with their product Dita Matting. Tiles can’t be installed over an acoustic floor without an anti-fracture membrane and flexible adhesive. The movement in the acoustic flooring would cause grout lines to crack without these two things. Whichever one of the Hush Acoustic flooring products is specified, the correct anti-cracking solution must be specified.

Hush timber/cement particle topped acoustic flooring has been tested with the anti-fracture membranes listed above. Therefore, specifying Hush Panel 17, Hush Panel 23, Hush Panel 28, Hush Panel 32, Hush Panel 33, Hush Panel 37, Hush Panel Premier, Hush Cem Panel 28, Hush Cem Panel 32 Hush Ply 28 and Hush Ply 32 is fine under tiles with the correct anti-fracture system.

Hush Cork/Rubber underlay has also been tested under tiles with the correct anti-fracture membrane.

If a plywood deck is to be used as a layer to support the tiles, over the acoustic flooring, then this plywood still needs to be treated with the correct anti-fracture system. The plywood alone is not enough to guarantee prevention against movement issues.

All Hush FFR underlay, Hush cork/rubber underlay, Hush overscreed or Hush Mat products have been tested under plywood and an anti-fracture membrane to prevent movement issues with a tiled floor finish.

Vinyl and LVT floor finish

Vinyl floor finishes are particularly difficult to get right when laid in conjunction with an acoustic floor. This is due to the movement in the floor and if the flooring has joints then excess movement will transfer the joint lines through to the vinyl floor finish. Hush has an underlay product which is called the Underlay for Vinyl Flooring. This product can be used under vinyl or lino type floor finishes. As long as the floor finish is not pure PVC (no vinyl in the UK should be) then the 3mm Underlay for Vinyl can be laid directly under a vinyl/lino floor finish. For LVT floor coverings we have a Hush Underlay for LVT that can be used directly under the LVT finish.
Should the development need a more substantial acoustic flooring to go under a vinyl or LVT finish then the timber/cement particle flooring products can be used under vinyl floor finishes but only if the correct preparation is used to the acoustic flooring to take the floor finish. As a guide only, Hush recommends the following when installing the vinyl over a timber/cement particle topped acoustic flooring:

Install the Hush Acoustic flooring product in line with the correct installation guidance.
Over board the acoustic floor product in the opposite direction, with a 6 or 9mm plywood (contractors choice of suitability for the floor finish).
The plywood sheet to be screw fixed tight to the top of the acoustic flooring. For the cement particle topped products a pilot hole will need to be drilled prior to screwing.
The screw fixings to be at a maximum of 300mm centres but should be at contractor’s choice to suit the floor finish.
When the plywood is installed, all joint lines on the plywood to be sealed with a filler compound and all screw heads filled to prevent transference through to the floor finish. This filling to be sanded smooth if needed prior to installation of the vinyl.

We have worked on many sites and seen occasions that the flooring contractor does not wish to overboard the acoustic flooring with plywood before the installation of the vinyl. This has been the choice of the main contractor, sub-contractors and the design team. If this is the case, then the same filling solutions and sanding smooth the joints of the acoustic flooring needs to be carried out before the vinyl is laid.

The Hush Acoustic flooring product must be installed as per the manufacturer’s guidance.

Carpet tiles

Carpet tiles is another floor finish that does not lend itself well to acoustic flooring. The main reason for this is the many joints in a carpet tile flooring. Should the floor move then the carpet tiles will lip and become a trip hazard. A bespoke build up is normally recommended for carpet tiled floor finishes, this is listed as follows:

– Ensure the structure is solid and free from much deflection.
– Bond the Hush 3mm Hush Cork/Rubber Underlay over the structure.
– Install a Hush 18mm T&G Flooring Grade Plywood sheet as a floating floor over the underlay. Ensuring the joints are glued with Hush Bond Adhesive and all perimeters are isolated using Hush Seal 20.
– Overboard the Hush Plywood 18 with a 6mm plywood sheet. The 6mm plywood to be installed the opposite way to the 18mm plywood. Ensure the 6mm plywood is screw fixed to the 18mm plywood only and not into the underlay. The 6mm plywood to be sealed at the perimeters using Hush Acoustic sealant.
– Ensure the joints and screw heads are sealed with a filler compound and sanded smooth if needed.
– The carpet tiled floor can be bonded to the top layer of 6mm plywood.

The Hush Acoustic flooring product must be installed as per the manufacturer’s guidance.

Parquet flooring (traditional herringbone fashion

Parquet flooring can be an issue due to the multiple blocks used to create the flooring effect. Should the acoustic floor be too resilient then there will be an issue with the blocks coming apart. Due to this, the following solution is recommended for laying parquet flooring:

– Ensure the structure is solid and free from much deflection.
– Bond the Hush 3mm Hush Cork/Rubber Underlay over the structure.
– Install a Hush 22mm T&G Flooring Grade Plywood sheet as a flooring floor over the underlay. Ensuring the joints are glued with Hush Bond Adhesive and all perimeters are isolated using Hush Seal 20.
– Overboard the Hush Plywood 22 with a 9mm plywood sheet. The 9mm plywood to be installed the opposite way to the 22mm plywood. Ensure the 9mm plywood is screw fixed to the 22mm plywood only and not into the underlay. The 6mm plywood to be sealed at the perimeters using Hush Acoustic sealant.
– Ensure the joints and screw heads are sealed with a filler compound and sanded smooth if needed.
– The parquet floor can be bonded and nailed to the top layer of 9mm plywood.

The Hush Acoustic flooring product must be installed as per the manufacturer’s guidance.