My Sound Deadening project for T27 (outside UK)

[Jack Levi]

You can't reach through the openings of the front doors with your hand.

Insulation mat is for camping cars and it is a quite expensive.

Natural rubber is intended as waterproofing for outdoor use.

The geotextile is lightly piled.

Undercoating to all wheel housing.

The car feels quieter now.

[Morton54]

Beeing "allergic" to road noise I did some work on my Avensis 2018 a couple of years ago.
After a lot of internet reading I learned that those who invested a lot of hours and expensive materials, stripping the interior and so on, came to the same conclusion. The job is not worth it. Car noise are compiled of too many sources and when you manage to mute one another will take over. So my idea was to make it simple and hope for an improvement.

 The last Avensis was in fact rather quiet as delivered. If driven smoothly that is 😉. But I covered the inside of the doorpanels with some self adhesive sound deadening heavy 2 mm rubber sheets (Carbest Alubutyl). That surely had some positive effect. The sound of Speakers also improved a lot and the feeling of the door closing was more premium like. Then I simply covered the floor under all the car mats with the same stuff. The trunk was fitted with a 10 mm NBR closed cell rubber mat (Forget fancy expensive car products. Gym mats comes in the same material). Finally I covered the accsessible firewall and the bonnet with NBR.  All this made the Avensis sound a bit more tight and quiet.    
But the biggest difference came when I swapped the original Bridgstone tires with Falken - Ziex ZE310 Ecorun 😄.

All in all this last Avensis model is now such a pleasant car that I dont look forward to the time when I have to replace it. It's going to be an expensive buy to match this car... 

[Bper]

How long did it take you to do and how much did it cost. Many members would also like to cut our road noise etc so it will give them a good idea.

As you say the biggest difference as changing the tyres. Well done for the effort you put into in doing this.👍

[APS]

Does the fabric hold water? I'd be worried that you have created a kind of sponge that retains water in the doors and speeds up corrosion.

[Morton54]

I used one saturday to do it I think. 

The Alubutyl (made for isolation of caravans) is kind of asphalt rubber layered with aluminum sheet so moisture and water is no problem. It acts as a sound blocker and vibration damper (low frequences).

Rubber mats has to be closed cells type. If not it will be a sponge. The NBR rubber was choosen because it is resistant to acid and oil and withstands high temperature. They are typical sound absorbers. Neopren (like in dive suits) is maybe the best absorber, but much more expensive.

Using both these types of material as a sandwich gives the best sound isolation. I did that on the entire floor under the car mats, but in the door panels I used only the 2 mm Alubytul.     

If I remember correctly I used three rolls of Carbest Alubutyl (100x50), about 14£ each. And 3-4 NBR mats (160x80). You can find them down to 10£ I think. 

[Bper]

This link may be interesting to anyone looking to soundproofing their  own car it describes the best materials available.👍

https://yourcar.co.uk/best-car-sound-deadening-material/

[Morton54]

Yes, It's a tremendous amount of expensive products out there all claiming to be the best. But for the average owner many of these sound deadening projects are way too complex and out of the question. It involves stripping the complete interior etc.
The point of Mr Levis' project, and mine, is what can be done by relative simple means by yourself. And I still claim, based on what other people have experienced, spending a lot of time and money  on this is not worth the result. At least not on a cheaper car. And if you own a newer BMW, Audi or similar car you certainly not want to mess with it. 

[Bper]

11 hours ago, Morton54 said:

Yes, It's a tremendous amount of expensive products out there all claiming to be the best. But for the average owner many of these sound deadening projects are way too complex and out of the question. It involves stripping the complete interior etc.
The point of Mr Levis' project, and mine, is what can be done by relative simple means by yourself. And I still claim, based on what other people have experienced, spending a lot of time and money  on this is not worth the result. At least not on a cheaper car. And if you own a newer BMW, Audi or similar car you certainly not want to mess with it. 

Hi Morton, 

I understand that you have used simple materials and it highlights what you can do without spending fortune's, well done for doing so. However some members who read this post may not be aware of the different types of materials available. It's more about awareness and choices available should they wish to spend a bit more and go down an alternative material soundproofing route.👍

[avensis_2018]

it took me 5-6 months + around 1000$ to make this car dead quite (doors\rugs\seats\dash\trunk\hood ++++++.

but it worth it !

[Morton54]

11 hours ago, avensis_2018 said:

it took me 5-6 months + around 1000$ to make this car dead quite (doors\rugs\seats\dash\trunk\hood ++++++.

but it worth it !

Congrats.
As  I said, the 2018 Avensis is allready a very quiet car with the right tyres on good roads. After my 1-day modification, it's clear to me which noise sources are still bothering me. Road/wind noise in high speed and engine sound when revving. But it's also these which are most complicated to fix.

Impressive piece of work though. Requires some courage to start on this. 👍