Sheep's wool vs Thinsulate

Hey there! I haven’t ordered the insulation for our Promaster 159 xt HR…I’m back and forth between wool and thinsulate. Thinsulate seems way more expensive, but we can apply it to the ribs and it’s (more?) durable, whereas the sheep’s wool option looks more cost effective, hydrophobic and can be stuffed into cracks easily.

Thoughts? And please, refrain from replying with “just park in the shade.” We will be living in this full time starting this summer.

Go to insulation section. Unfortunately their site has been redesigned since my last visit and it usually does not get better when that happens.

That’s polyester wool, made from recycled plastics. In vehicle use it has several favorable qualities, such as it won’t burn easily, it doesn’t get wet or mold, it dampens sound and is a thermal insulator. That particular brand is their own design but I’m pretty sure someone else has similar product elsewhere available.

It is widely used here in automotive retrofitting, ie. shops that build taxi vans, police and ambulance vehicles etc from regular vans. From there it has also spread to those who build their own campers. Other uses are obviously in construction and people who build their own speakers.

Thinsulate is also a brand name for certain 3M product. If there is a competing product with similar features it will have a different name… making it quite difficult to find.


If you really want insulation, I would suggest that you get the best for sound deadening. None of it works good enough for temperature control to make it worth the cost or effort, and in many instances the negatives far outweigh any positives.

If you focus on sound deadening, it can make an especially huge difference while driving. It’s also important to cover all interior metal surfaces to create a thermal break between the outside skin and the interior. It takes very little exposed metal to have a large negative effect. Most people use automotive carpet, perhaps trunk carpet, which is similar to felt.

It should be mentioned that only active heating & cooling can keep you comfortable year round. Both can be cheap, easy, and extremely energy efficient. I can expand on that if needed.


"If you prepare for the worst, every thing else is easier." ~ Off Grid

Any thoughts about Rockwool?

I think both are good choices. We used wool, but I know a lot of people that use thinsulate and are happy with it. A lot of people I see add some sound deadening stuff to the walls before insulating. We choose the wool as it’s supposed to generate heat when wet. My thought there was it would help dissipate it as we choose not to build a vapor barrier. With a fan we’re pretty comfortable right now. It’s around 100ºF out at the moment. In the winter we were pretty comfortable with a heater. If you have a ton of windows it probably won’t matter either way. We did notice a pretty large reduction in sound with the wool. It’s supposed to be good for that. If you look at the havelock site they have a whole page dedicated on why to use it for vans over the other options. Overall we’re happy with it, but I think the wool is probably more work than the other options as well. We basically sewed ours in until we added framing and walls to hold it there.

I haven’t used the wool, but used thinsulate in my build and am very happy with it. However it isn’t the only thing I used. I covered the entire interior with thinsulate (other than the cab area, but I got as much of that as I could) and in most places also used XPS or Polyiso panels under my walls. As a consequence I am very comfortable in the cold and can keep it cool without running my AC too many hours (It draws about 35 amps out of the batteries while running).

Very happy with the thinsulate as the base insulation in my vehicle, it made a huge difference even before adding the additional foam sheets.

Wool doesn’t generate heat when wet. If it did, you could collect well cooked sheep from fields after thunderstorm. :wink:

Actually it retains its ability to insulate even when wet, ie a wool sweater keeps you warm even if you dip into a river wearing it and a wet cotton shirt will make you colder in same situation.

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In over 40 years of being a nomad, I have lived in many different rigs, mostly factory camper vans or RV’s. All with questionable amounts of insulation, if any at all. Largely do to my work, I spent winters in arctic temps, and summers in both hot and often hot & humid conditions.

For one year, I had a self converted cargo van, converted by me, following directions from supposedly experienced people online. It had far more insulation and far fewer windows than any of my other rigs. I started out with two very expensive Fantastic roof vents, a Big Buddy propane heater, and a 10k BTU air conditioner that required either shore power or a generator. After freezing my butt off with the Big Buddy heater, I upgraded to a very expensive vented propane heater. Other than condensation, it wasn’t much better. Please keep in mind that I had already spent many arctic winters quite comfortably and affordably in other rigs. That heavily insulated cargo van cost me about 3x more to heat, and I was still always miserably cold.

Summers weren’t any better, that 10k BTU air conditioner just couldn’t keep up. PLUS I was paying for campsites with power. The shortest version of the story is it was miserable, and costing me considerably more to be miserable. Indoor climate control in that thing was nearly impossible in extreme conditions. Something I have never experienced either before or after that cargo van.

Looking back, my failure was multi-faceted. All because of my online mentors who turned out to be nothing more than sleazy sales people, who couldn’t care less about my comfort or safety. The cargo van was only the first in a long line of very expensive mistakes. I had tons of very expensive equipment, and a very expensive build, but I didn’t have the much cheaper right equipment, or any good honest advice. It was the worst rig of any, and I lost over $30k in the year I owned it, just in hard cash outlay, and not even counting my countless hours of work. The insulation didn’t help, and if anything worked against me.

Successful climate control consists of three components, proper ventilation, proper heating, and proper cooling. Proper ventilation can not be achieved in a cargo van without leaving the the doors open all the time. Many opening, adjustable windows are a far superior choice to roof vents. Roof vents don’t help enough, and the open doors defeat any heating or cooling efforts. Insulation doesn’t help no matter how you you slice it, because proper ventilation totally defeats any supposed advantages of insulation.

Heating is pretty simple, you need enough heat (BTU’s) to keep you comfortable, and it needs to be dry heat.

Cooling can be nearly as simple if we look in the right direction. In hurricane, tornado, and many rural areas, you can go without electricity for many days, even weeks, and off grid you need to generate all your own power, just like many of us. So the mainstream choices are a generator or battery power. Generators work, but unless they’re built in, like in an RV, they aren’t very convenient. To our advantage, powerful, energy efficient cooling can be provided by battery power, in the form of swamp coolers. They can be bought or built to run on 12v and consume under 2 amps of power. There are different designs, including ones that work in humid climates, I have one, and use it regularly.

If you need climate control, do it right to begin with, it will save you a lot of time, money, and frustration in the future, and insulation is not one of the necessary components. Ohhhh… Did I mention the condensation, mold, and rust issues that insulation caused me?


"Be a trendsetter and support yourself !!!" ~ Camp4Ever

@KLF - Perhaps I misinterpreted this but, from the havelock site:

“Wool prevents condensation by generating heat from energy, making it warm when wet.”

And from some other research (

“Inside the wool fiber, water vapor binds to the cortex, producing the heat of adsorption . Again, all adsorption is exothermic …heat generating.”

So maybe it does generate some bit of heat?

I tried to look for more info but I literally found only some scientific research how carbon molecules behave in different temperatures. I mean, something that would point how it is beneficial to have wet wool insulation vs. other types dry. Or even dry wool.

I decided to go with closed cell spray. It IS more expensive , however I won’t need sound deadener NOR moisture barrier! That will save a bit off the price tag. The R-value is pretty amazing and the structural support it gives will allow for a more sturdy roof and INCREDIBLE r-value at the roof. It’ll be about 6 inches thick there.