Vans are noisy.

Rear view of van with sound deadening installed on ceiling, walls, floor, and wheel arches

Sound travels through from the floor, the walls, and even the roof.

The thin metal panels vibrate when driving which can feel like a rattle inside your head.

Road noise and the engine can also make it difficult to talk or listen to music.

Sometimes you even can hear word for word conversations outside or get startled by footsteps when sleeping at night.

All of which doesn’t exactly make the van feel like home.

So we started looking into solutions to help with external noise and came across sound deadening.

What is Sound Deadening?

Sound deadening is a soundproofing material that absorbs the vibrations and energy that create sound waves, providing a sound dampening effect.

There are different types of sound deadening, including butyl rubber sheets, vinyl or foam underlay mats, tape, paint, spray, and more.

Some of these provide better sound proofing than others.

There seems to be a wider variety of sound deadening suppliers in the States than in Australia.

We looked at sourcing Kilmat or Dynamat from the U.S., but the cost of shipping almost equalled the cost of the product.

We Eventually Found a local Aussie supplier: car Builders.

Car Builders sell butyl rubber sound deadening sheets topped with an aluminium layer.

Butyl rubber is inherently sticky, doesn’t crack, and it’s easy to install.

Apparently, these sheets have both acoustic and thermal benefits.

It’s a funny material to play around with.

Watch out it doesn’t stick to any clothing in the install process!

There are a whole series of steps that can ‘optimally’ sound deaden a van (according to Car Builders).

But to be as economical as possible, we just went for the sound deadening sheets.

apparently, all you need is 25% coverage to get a noticeable sound dampening effect.

But it’s recommended to have 60% or more.

so, Does sound deadening make a difference?

Yep, we think so.

After the install, we found there was a very noticeable difference.

Particularly with the vibration of the metal panels when driving and external sounds when parked at night.

It was also easier to talk to each other on the road and we didn’t have to play music so loudly.

Unfortunately, we didn’t do a more objective test to measure exactly how much difference sound deadening makes.

were we just trying to convince ourselves there was a difference, or was there a real change?

All the “objective” evidence we have is a video of Peter knocking on one side of the van that has sound deadening, and the other which doesn’t.

Van builder tapping walls of van with and without sound deadening

So, we started researching.

Lots of people have tested their sound deadening.

Whilst the results were inconsistent, there seemed to be some consensus:

sound deadening apparently reduces noise by ~5-10 decibels.

But it got us wondering, what exactly does that mean?

We wanted to better understand what difference sound deadening ACTUALLY makes.

Let’s nerd out on sound for a bit.

The decibel scale has been the standardised method used to measure sound (and a few other things) since the 1920s.

The ‘bel’ was named in honour of the infamous Alexander Graham Bell. The scale was originally devised to measure signal loss (or transmission efficiency) in telegram and telephone communications, but is commonly used today to measure sound.

To understand what the decibel correlates to in the real world, we looked into what decibels correlate with.

A whisper is about 20 decibels, whereas a music concert is about 110 decibels.

Here’s a table of the decibel level of more everyday sounds:

Table of decibel levels of everyday sounds — Read more here and here.

But DECIBELS AREN’T the same as loudness.

Because The decibel (dB) scale is logarithmic.

The equation for a decibel is:

dB = 10*log10(P2/P1), where P is power

Maths is not my forte, so I like words…

For those like me, this calculation says:

A 10 decibel increase means the sound wave is 10x more powerful
A 20 dB increase means the sound wave is 100x more powerful
and so on…

But If something is twice as loud, it doesn’t necessarily correlate with double the decibels.

This is because of the log scale relationship of the decibel.

So, the science world had to work out how an increase in decibels relates to loudness.

How did they do this?

By simply by asking people how loud they think a noise is at a given decibel level.

And the results?

Every 10 dB increase equates to double the perceived loudness.

And the inverse is true too with a 10 dB decrease.

So, what does a reduction of 10 dB from sound deadening mean?

Well, it corresponds half the loudness.

In other words…

sound deadening can potentially Cut the loudness in A van by half.

Not bad.

Not bad at all.

(Please note this is just a rudimentary calculation based off limited information. It’s not a perfect experiment — the idea was just to get a rough idea of the real world impact the sound deadening makes!)

Installing sound deadening in our van

For our van, we only budgeted $50 AUD for the sound deadening (this was before we even knew what sound deadening was). But this was quite off.

We quickly realised sound deadening is expensive.

But we felt the benefits outweighed the cons.

So, as it goes, we flexed the budget.

As a result, we had to be economical with our purchase.

This meant we probably got less than we needed and we would definitely grab a few extra boxes next time for better results.

But we are still happy.

Interior design of Renault Master van from vanspace 3D — Attie the Van

How To Install Sound Deadening

Car Builders have videos and guides on how to install their sound deadening.

Here’s how we did it:

1. Calculate THE COVERAGE

Before ordering the sound deadening, we calculated the square meterage of our Renault Master van.

We figured the van had around 15 sqm of surface area where the sound deadening would have an impact.

[Note, we already had some factory sound deadening in place, and we removed from our calculations specific areas where the ceiling fan, window, etc. would go.']

To cover roughly 25% of the van, we’d need ~4 sqm of sound deadening.

So we bought 2x boxes of sound deadening. Each box of Car Builders sound deadening is 1.8sqm, with 12 sheets measuring 50cm long x 30cm wide x 2mm deep.

Front entrance of Car Builders business — Car Builders in Kilsyth, Victoria

2. Clean the van

Before starting the install, it’s important to clean any surfaces to ensure proper adhesion of the butyl rubber.

We made sure to remove any dirt, dust, or grease.

And that everything was dry before continuing.

3. Allocate The Sheets

We strategically allocated our sheets to make the most of what we had, aiming for at least 25% coverage in the most important areas.

As the large sheet metal panels create the most vibrations and noise, we aimed to cover these well.

And other areas less so where it wasn’t needed as much. For example, we didn’t put sound deadening where we are going to cut out part of the van for a fan or a window. We also avoided areas that we are leaving with the factory finish (like parts of the doors that we aren’t going to cover with anything).

Getting more sound deadening would make this allocation easier, but it also costs more and weighs more!

Rear view looking into van with sheets sound deadening laid out and dog in background — Little Zeze (our foster dog) overseeing the process, as always.

As you can see, we made sure our site manager was on location throughout the process.

A very important step!

4. Installation

We followed three main steps during the installation:

Cut the butyl sheet to size (with plain old regular scissors)
Cutting the strips for the floor was easily the most time-consuming part of the process. Car Builders have dotted lines on the backing of the sheets to help with this. Be sure to wear gloves because the aluminium edges can be sharp!
Remove the backing and stick the sheet on the wall
Go nice and easy with this because once it sticks on, it’s not coming off anytime soon. We started with the walls (it seemed to be the easiest place to start because we’d never done it before). We then applied it to the roof, the floor, and the wheel arches (probably the hardest part).
Roll the sheet onto the wall to “smush” it and ensure proper adhesion
We used an ice-cream scooper and a wooden block for this, but Car Builders sells the proper tool on their website.

Butyl rubber takes a bit of getting used to.

It wasn’t perfect, but we are pretty happy with the results!

At the end of the process, we were covered in the butyl rubber.

Next time, we’ll be choosing our work outfits better and will wear gloves to save our hands.

Update:

5. Handling the stickiness

Whilst we were still building the van, we wanted to go on weekend getaways and adventures. So we had to come up with a way to stop the butyl rubber getting on our stuff (sleeping bags, clothes, dog bed).

So we got some Ametalin Insulation Tape to cover the wheel wells and block any butyl rubber escaping.

A great solution for a sticky problem.

How long does it take to install sound deadening?

For our van, we thought it would take 2 hours to do the sound deadening.

In reality, it took 5+ hours. Mainly spent allocating the sheets and cutting the sheets.

I’m sure once you get used to the material, you could do it much, much faster.

Why Do some people decide not to install sound deadening?

There are also some reasons people choose not to install sound deadening:

People argue the van will always be noisy when you drive anyways, especially if there is cutlery rattling and squeaky doors. This may cancel out the beneficial effect of the sound deadening.
Sound deadening can add extra weight, especially if you do it properly and use the correct coverage. Each 12 sheet box weighs around 6kg.
It’s expensive. It costs $104.99 for 1.8sq/m. And the research isn’t conclusive about exactly how effective it is. Who really knows how much benefit it gives for every dollar invested!

How much does sound deadening cost?

We spent $181.10 on sound deadening for our van. But could have easily spent more to get better coverage.

Here’s the breakdown:

Table of cost breakdown for sound deadening in a van

Costs add up pretty quickly with sound deadening. Of course, you could go all out and install it everywhere, but we decided against that because it would be very expensive (especially for our already maxed budget).

Sound deadening is definitely a bit of an investment.

But if it can potentially reduce noise pollution when driving and help you get a better night’s sleep, it’s definitely worth considering.

Particularly for anyone travelling a lot or living in a van full-time to make it feel more homely.

In the end, we are happy we installed sound deadening in our van!

Sound deadening on interior walls and wheel arch of van