[pjtezza]

As an accidental experiment, I just spent 2 weeks and 2,000 miles driving circles around California in my uninsulated camper van.

I have a low roof Transit that has been converted (seats, cabinets, popup top, etc..) but is basically uninsulated - there is a bit of covering on the walls (coroplast plastic) and I have a popup top with some insulation, but I don't have anything at all inside the walls and the floor is still stock black plastic over thin insulation.

Soundproofing and Road Noise

Like many here on these forums, when I first bought my empty cargo van, soundproofing was on my mind a lot because the van was very noisy. However, now that I've added my (insulationless) conversion, I've noticed that, at least in the driver's seat at 50MPH and up, the wind noise from the side mirrors is much louder than anything inside my van. Fortunately, as I like my side mirrors, a little music from the radio easily overcomes the wind nose. Since, even without any insulation, unavoidable wind noise is the limiting factor in a quite ride, soundproofing beyond whatever comes from insulation seems superfluous.

R-Value is What Counts

During my trip, I mostly camped with lows in the 40s and 50s. However, I spent a few nights with lows of 5F in Bridgeport and Bishop. Here, I learned the importance of R-value. I have a relatively small 7,000BTU propane furnace mounted under the van. The furnace blows out very hot air and the vent is strategically placed. The system worked fine at 45F, but, at 5F, without insulation, it couldn't keep temperatures inside of the van warm - I'd estimate the temperature at my bed was 50F while remote parts of the van were colder. Also, I realized that as there is only 1 vent, without good insulation, it won't be possible to evenly warm the van.

Also of note: The stock floor was very cold. My 5 gallon water containers inside the van didn't freeze, but my water pump, mounted in the passenger side wall, froze. Fortunately, the water pump worked again once it thawed.

 

[EddieZ]

I have a relatively small 7,000BTU propane furnace mounted under the van. The furnace blows out very hot air and the vent is strategically placed. The system worked fine at 45F, but, at 5F, without insulation, it couldn't keep temperatures inside of the van warm - I'd estimate the temperature at my bed was 50F while remote parts of the van were colder. Also, I realized that as there is only 1 vent, without good insulation, it won't be possible to evenly warm the van.

Also of note: The stock floor was very cold. My 5 gallon water containers inside the van didn't freeze, but my water pump, mounted in the passenger side wall, froze. Fortunately, the water pump worked again once it thawed.

As I understand it, propane burn (and/or flow from the tank? Something...) becomes less efficient at lower temperatures, which would account for part of the diminished returns.

 

[orton]

If you have a house battery, a 12 volt heating pad works very well.

 

[klp]

My analysis is about as scientific as yours but as someone who has insulated the Sh#@ out of my van I think it does make a difference. The cld tiles reduce and change the frequency of vibration - if you apply enough you get a much more solid feeling vehicle.

I did not notice a big difference in sound when I added the thinsulate, my biggest gains were the floor with mlv/cc foam and the tiles throughout.

 

[dustboy]

I have been surprised at how effective the reflectix has been. Even though the r-value is apparently paltry when applied directly to the sheetmetal as I did, it did make a very noticeable difference.

I am not willing to add any more thickness to the insulation as headroom and interior volume is precious.

I also noticed that adding the cheap HD short-nap carpet over the reflectix made a big difference in the road noise. The carpet dampens a lot of the noise that is otherwise bouncing around. I now know why those 70's conversion vans were covered in that deep shag carpeting.


Sent from my iPhone using Tapatalk

 

[Hein]

Pjtezza,

We hope you are aware that 3M Thinsulate(TM) will provide noise and thermal insulation in one easy to install, no mess, safe product that is engineered for vehicles and passes FMVSS-302 for flammability.

So there is no need to prioritze between sound proofing and Thermal R-value. With Thinsulate(TM) you can have both.

Please pm or call to request a sample.
All the best,
Hein
Impact, Inc.
Hood River, OR
54l 49O 5O98

 

[surly Bill]

When people want to "soundproof" what they are trying to eliminate is road noise. A parked van doesn't make much noise.

It seems to me the biggest road noise elimination gains would be in the wheel wells and the floor. Maybe the firewall. Rattling and sympathetic vibration of sheet metal panels would be next (a single square of deadener in the middle takes care of that). It's probably a waste of time and money to use sound deadener above the wheel wells. 3M thinsulate in the walls and ceiling would take care of thermal AND sound issues.

What people think is a problem with sound penetration may actually be sound reverberation. Notice when you walk into an empty house how loud it is? Notice how after you've put in furniture and some stuff how much quieter it is? Sound waves absorbed, defracted, diminished by a whole bunch of random surfaces. A cargo van with bare walls or hard panels is ALWAYS going to be loud. Take a tip from furniture movers, hang moving blankets over the walls (S hooks into grommets in the blankets) to absorb interior sound AND protect the walls.

 

[BabyBuffy]

" It's probably a waste of time and money to use sound deadener above the wheel wells."

I'm in a stage of development with the new van where the topic of sound insulation is a sacred matter...

The op's subject line is like someone screaming loudly in a theater to me but apart from that...

By "above the wheel wells" what do you mean? Atop the wheel wells, or further up the wall above the wheel wells? Which wheel wells, and why do you say that?

 

[pjtezza]

Soundproofing doesn't matter because all I can hear from the driver's seat at 60+ MPH is wind noise from the side mirrors. If you could somehow reduce the wind noise to the point where it doesn't drown out the road noise, then it might make sense to try and reduce the road noise.

If you anticipate a lot of driving below 60MPH, you plan to drive around with your van empty often and/or your side mirrors aren't as noisy as mine, then reducing road noise might be a reasonable priority. Otherwise, R-value is the only reason to insulate your van. If you don't need R-value, you could forgo insulation altogether and have about the same amount of ambient noise at 60MPH (assuming you have an amount of stuff in your van comparable to my conversion).

 

[BabyBuffy]

Soundproofing doesn't matter because all I can hear from the driver's seat at 60+ MPH is wind noise from the side mirrors. If you could somehow reduce the wind noise to the point where it doesn't drown out the road noise, then it might make sense to try and reduce the road noise.

If you anticipate a lot of driving below 60MPH, you plan to drive around with your van empty often and/or your side mirrors aren't as noisy as mine, then reducing road noise might be a reasonable priority. Otherwise, R-value is the only reason to insulate your van. If you don't need R-value, you could forgo insulation altogether and have about the same amount of ambient noise at 60MPH (assuming you have an amount of stuff in your van comparable to my conversion).

What you say is incomprehensible to me. There is a phenomenon by which random background noise makes something audible that otherwise you wouldn't be able to hear. It's because the patterned noise normally at a level below your hearing threshold is raised above it by being reinforced with the uniform underlying white noise. It could be that the road noise you say is masked out by the wind noise is because of that reason. Not that the mirror noise is below your hearing threshold without it but it becomes the loudest thing for you to hear. I've driven my van on the freeway and it is noisy as aitch double ell. It won't be when I'm finished or I'll jam ice-picks into my ears.

 

[pjtezza]

What you say is incomprehensible to me. There is a phenomenon by which random background noise makes something audible that otherwise you wouldn't be able to hear. It's because the patterned noise normally at a level below your hearing threshold is raised above it by being reinforced with the uniform underlying white noise. It could be that the road noise you say is masked out by the wind noise is because of that reason. Not that the mirror noise is below your hearing threshold without it but it becomes the loudest thing for you to hear. I've driven my van on the freeway and it is noisy as aitch double ell. It won't be when I'm finished or I'll jam ice-picks into my ears.

The concept is not difficult to understand: If you are at a Metallica concert, you can't hear somebody 3 rows away from you whispering because of the loud "music". Your van is noisy because it is empty. Put some stuff in it and then the dominating noise at 60MPH, by a large margin, will be wind noise.

 

[BabyBuffy]

When my empty van is parked, I don't hear any noise. The sound that bounces around inside of it when it moves comes from somewhere. It gets in there many ways having to do with movement and causing resonant vibrations, among other things. It is flying in the face of common sentiment to suggest nothing can be done to modulate those sounds.

After the Metallica concerts I've attended I couldn't hear someone talking to me period for awhile.

 

[pjtezza]

When my empty van is parked, I don't hear any noise. The sound that bounces around inside of it when it moves comes from somewhere. It gets in there many ways having to do with movement and causing resonant vibrations, among other things. It is flying in the face of common sentiment to suggest nothing can be done to modulate those sounds.

After the Metallica concerts I've attended I couldn't hear someone talking to me period for awhile.

I'm not suggesting that nothing can be done. I'm suggesting that your conversion will be enough to modulate those sounds below the threshold of hearing unless you can figure out a way to reduce the wind noise.

My empty cargo van was also very noisy, but, after I got my conversion in, I noticed that the conversion alone, without soundproofing or even insulation, was enough to reduce all other noises below the level of the wind noise.

In my case, this discussion is not theoretical. I drove my empty cargo van around for about 2,000 miles - it was noisy. I installed my conversion without soundproofing or insulation and just drove it for 2,000 miles - on the highway, the main noise I hear is wind noise from the side mirrors.

 

[BabyBuffy]

OK, well that's something I'll never know because I'll never get to hear what my converted van would have sounded like without sound insulation.

My philosophy is usually, when in doubt go for overkill.

 

[pjtezza]

OK, well that's something I'll never know because I'll never get to hear what my converted van would have sounded like without sound insulation.

My philosophy is usually, when in doubt go for overkill.

"premature optimization is the root of all evil" -- Donald Knuth

 

[surly Bill]

Baby; I mean the walls above the wheel wells. ABSOLUTELY try to stop sound at every exposed part of the rear wheel wells, and under the floor mat at the front wheel wells. With the new availability of wheel well liners to keep junk from the tires out of crevasses, using an external soundproofing between the liner and the metal would be a good idea as well.

as stated, using the thinsulate on the walls and ceiling should be more than enough soundproofing for a parked van. Road noise from tires and wind noise from...wind...are the major noise sources when driving. The engines are pretty quiet.

Hauling 4 bed/boxspring sets in my Sprinter was the quietest it ever was. NO sound bouncing around inside.

 

[skagitstan]

Our primary goal for insulation was thermal. But before we did any of our mods, noise level was quite high. It was hard to make out the radio, and conversation was difficult...had to shout.
A lot of road/tire noise and wind noise. A lot of the road noise was coupled through the floor and wheel wells. Mirrors did not seem to be the worst of the wind noise. We have short mirrors.

The only specific sound treatment we did was thinsulate on the rear wheel wells. That made a noticeable improvement.

Everything else that we did for thermal (ISO on the ceilng, the raised and insulated floor, Thinsulate in the walls, etc.) also made significant improvements in noise levels.
Interestingly, other mods made a difference as well. For example, the solar panels seemed to reduce wind noise. I installed them before I insulated the ceiling. I suspect the improvement's because the panels move turbulence away from the roof, and only let it couple back into the van at the rack attachment points. The internal construction (bath, fridge area, etc.) also seems to have helped.

At this point (and we're not done) Annie's noise level is very acceptable. I wish I had made some before/after measurements.

My point is that it's likely most noise improvements are incremental in a campervan build, incidental to the other work done. Exception being decoupling wheel/tire noise at the wells.

Stan

 

[atoine]

We added CLD tiles on every unsupported panels (about 20-30% coverage if i recall) and we also added MLV sheet on the entire floor.

If we were to do it again, we would save the money, time & weight and NOT add these. We don't feel these provided significant improvements. Actually, we think the CLD addition made it worst. It seems that the "banging" of the closing doors and from road bumps would create a low-frequency noise that would just resonate for a while. I think Ford engineers did their job by adding CLD tiles sparingly. But that's my opinion.

The MLV sheet is HEAVY. While in theory it's suppose to absorb low-frequency noise (if installed properly, i.e. unsupported), we feel that the 1.5" thick insulating foam + plywood + vinyl floor would have been enough.

The wheel wells ARE noisy: we have not insulated them yet and we can clearly hear some noise when the pavement is wet. We will add Thinsulate and they will be enclosed in a cabinet later in the conversion.

Following our experience, what seems to really make a difference is: Thinsulate (or other thermal insulation), finished walls and furniture (cabinets, bed, etc).

 

[sschefer]

One thing for sure, there's definitely more than one way to skin this cat...

What seems to be working pretty good for me is three inch Denim insulation stuck on with 3M 90 spray adhesive. That's my insulation but I also wanted a good moisture barrier. On my first build I covered the entire interior, including the floor with Reflectix. The minimum R value of Reflectix when an air gap is not possible is R3 according to the manufacturer. I figured if I needed the moisture barrier anyway I might as well pick up a few R's at the same time. In my redo I used basically the same method but I did not panel areas that were not visible. I'm hoping to get a higher R value from the Reflectix in those unpaneled areas. It will be hard to know if I'm successful or not. The only test I've done so far was de-icing the windshield the other morning. It happened pretty fast compared to my 2014 F-150 that I was deicing at the same time. I don't know if the two are a good comparison or not.

As for noise level. It's pretty quiet for a van. It's not as quiet as my friends Bentley and I don't expect it ever will be.

 

[RonR]

This Transit is my third conversion. In my experience whatever you do for one (heat or noise) helps for the other. But, if you think about both you can get a better result for less effort and money. So this is what works for me.
* Deaden any panel that has a twang until it is a thunk.
* Add at least 1" of foam (spray or glue) directly to the skin.
* Fill the rest of the space with some soft insulation that will not transmit noise (Thinsulate, denim, whatever)
* Cover any exposed metal with at least cloth, better is 1/8" foam, then cloth.
* Make sure all doors and window gaps close. I add a thin layer of extra foam to most sealing surfaces and in some cases add a second sealing pair (foam on door and frame).
* Minimize the number of hard surfaces. I cover all the walls, ceiling and exposed metal in hulliner.
* The floor needs to carry a load so layers of different density materials is the best. I use 1/4 ethatfoam, 1" RMax, 1/4 recycled rubber, 1/2 appleply, vinyl.
* The wheel arches get an extra layer of soft spongy foam.

The goal is to seal all the doors, deaden any vibration, isolate the living space from the vibration and the heat, dampen any reflections.
Ron