Acoustic Insualtion ? Everything you need to know.

Do You have unwanted Noise coming into your home ?

Under floor insulated with Cellulose fibre before putting the plaster up (above left)

Wall insulated with cellulose fibre insulation by pumping it onto the wall with a spray gun that glues the insulation onto the wall (above right)

What can I do to stop the noise coming into my home?

Everyone likes to have the convenience of living near services that they need every day like Trains, Buses, Highways and Schools but not to many people like the noise from these services invading their home at all hours of the day and night. That is where a quality home insulation specifically designed for sound Attenuation in your external walls and ceiling might help stop these unwanted noises.

Insulation is a very effective solution for stopping sound and while Thermal insulation is measured in R-Value, Acoustic insulation is rated in terms of a Sound Transference Coefficient or STC Rating. Although, these ratings do have some approximate correlation, so it is important to understand that there is a different rating system for sound insulation.

Depending on the application sound insulation can deliver some very noticeable results but again, gaps in the insulation will be where the greatest losses of efficiency are made. For this reason it is recommended to use a quality pump in insulation like Cellulose Fibre when you want the best results. We can install this on existing walls as well.

How do I stop plane noise from coming into my home ?

Cellulose fibre pumped in insulation is much more effective at stopping overhead Air traffic or plane noise. One of the main reasons is that it is pumped in and so there are no gaps but the other major benefit is that it can cover the joist timber as well. Batt insulation just lays in the bays and it does not cover the joist, so the joists become the weak spot in transferring that plane noise into your home.

Have a look at the video below and you will see the difference it makes to be able to pump the insulation in and have such a complete coverage that the maximum sound that can be stopped is stopped.

Existing floor with kids upstairs & tenants downstairs. What do I do about the Noise ?

This is the type Question I get a lot for sound insulation between floors and this is my typical advice.

Question about sound insulation - We have a tenant that lives in the room downstairs and the noise from the people walking, kids playing or the vacuum cleaner scratching the floor is horrible!!. Can you insulate between my floors and how much noise will it stop?.

    1. The first thing to say is that it can be insulated by pumping cellulose fibre insulation into the floor cavity from below. We need to cut rows of 80mm holes across the floor about 1.5 m from the wall and every 450mm apart. Then we can move across the room about 3 meters and cut another row of holes the same. For example on a room 8m wide and 6m long we would need about 3 rows of 12 holes in the ceiling to insulate it.

    2. Our quote does not include the repairs costs of the holes and depending on the plasterer you use it would cost about $10-20 dollars a hole for the repair and painting.

    3. How much noise this will stop is a very subjective thing, I have insulated many floors over the years and regardless of what the sales people say, it is very hard to stop the bass noise of footsteps as the sound travels through the timber joists and comes out on the ceiling plaster like a drum. The only way to help stop this base noise is to have a rubber isolated ceiling installed after we insulate it but this could be very costly.

    4. The kinds of noise any in floor insulation will stop is the high pitch type of sounds, Talking, Radios, even the scratching from the vacuum but the foot steps thumping will mostly not be affected. Their may be some perceived difference in the foot step noise but only to the extent of the high pitch or scuffing part of the step.

    5. We would not recommend insulating the floor if you have any downlights or exhaust fans in the lower ceiling, these will need to be gaped around and with sound insulation just 1% gaps will reduce any benefit by 50%. If you have downlights then I would recommend removing them before we insulate the between floor area or you will ruin any chance of getting a result. If you do have your downlights removed, leave the holes there until we finish our job as we may be able to use some of them for the pumping of insulation.

    6. Although Cellulose Fibre is by far the best sound insulation for the same depth of product and because it is pumped in it is far more likely to fill the floor space completely with no gaps (unlike sound batts which suffer from gaps during installation and mice borrowing though them over time).

    7. Results from sound insulation can not guaranteed as the nature of sound transference is very difficult to stop and any results are subjective without a full sound engineers report before and after insulating your floor.


Just 1% Gaps in batt insulation Reduces the sound benefit by as much as 50 -70 %

This is where batts belong and it is where most end up, in the rubbish...

Our company has insulated many buildings for sound proofing including media rooms, night clubs, and radio stations. I have also insulated many homes in the flight path over the years and substantially reduced the noise of planes passing over or from constant traffic at your front door.

Sound insulation is a very specialised area of insulation, to get the best outcome for your sound problem it is best to get some qualified onsite advice.

Watch this Video and you can really hear the difference in the road noise now that it has been insulated !!

In Ceiling insulation helps stop sound like road noise too.

It is also worth mentioning that any noise problems you have can be helped with a quality In Ceiling insulation as well, people who live under Iron Roofs or Colour Bond Roofs will be very familiar with how noisy they can be during a summer down poor of rain. We all like the sound of rain on the roof but if you have to turn the TV up when its raining or you can not have a conversation without yelling, then insulation will help.


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