Let's talk insulation!

Van Living Forum

Help Support Van Living Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

VanFocused

Member
Joined
Jun 15, 2020
Messages
21
Reaction score
17
My favorite topic! Well... not really. Not at all. 

I spent so many hours of research when I was building out my campervan, and a good chunk of that was on insulation. Everyone has their own, drastically conflicting, opinions. And, outside of a couple points (like avoiding fiberglass insulation), nobody seems to agree on anything.

So, what did you all use for your insulation and why? I'll start.

Polyiso foam boards

I used polyiso foam boards (various thicknesses) for all the flat, panel-like areas. Poly iso ranges in R value from 3.2 for their 0.5inch to 13 for their 2inch. I mainly used 1 to 2 inch boards and it was the majority of the wall space and ceiling.

The cons of polyiso is that it squeaks. I was super concerned of the squeaks at first, but after I finished the build I realized that the whole damn van squeaks and creaks. 

The material was pretty simple to work with but does make a mess when you're cutting it. Cutting is simple enough. I just used a large razor blade and some sand-paper to sand down the sides so they woudn't get little pieces everywhere.

Installation is as simple as cutting to size and using 3m adhesive to stick it into place.

Rock Wool

Now this one gets a bit of controversy. After doing my research, I decided to go with rock wool. I used it to stuff into all the ribs and awkwardly shaped crevices. 

The R-Value for rockwool is around 3-3.3 per sq inch. Although you loose some of that if you over-stuff.

The Cons are that people CLAIM that rockwool absorbs moisture. From my research, I found this to be untrue. Rockwool claims to be hydrophilic, meaning that it does not absorb water at a molecular level. However, it is designed in a way that allows water vapor to pass through it. This means condensation can still collect on the cold metal walls of the van. Most insulations will allow this, without a vapor barrier, I believe.

All in all, I decided to go with it and I don't have any regrets (yet). 

The material was a little more annoying to work with. I am stubborn and not only did I not wear a mask (you really should), I also didn't wear gloves. It left me itchy for days. 

Spray Foam

The last material I used was spray foam, specifically great stuff single-part sealant that supposedly boasts a 6-7 R-value per square inch. I mainly did the gaps and cracks that were otherwise exposed. It still took a few cans though.

The Cons are the price, definitely. Spray foam is expensive. I also read (I don't know how true it is) that the chemicals in spray foam can eat away at the paint of the van and erode the metal. 

Installation was messy. I got that stuff everywhere. In my hair, my beard, on my freshly laid flooring (don't question me about my order of operations) and again I refused to wear gloves. That stuff is hard to get off once it dries.

Also of note

I didn't use a vapor barrier and I didn't insulate the floor.

So how is it holding up?

I'm now on my second winter living in my van full time. My first was in Missouri, where it would get down to the single digits often. This year, in Colorado, I've already hit 0 degrees F twice. 

I think all-in-all I spent way to much time thinking about insulation. My van is freezing when its cold out, if I'm not physically in there and running my heater. I don't mind the cold though, and I often sleep without the heater and just my 20 degree sleeping quilt and down booties (my feet get cold). 

I only wish I insulated the floor. Especially in windy CO, I think the wind rips right under my van and sucks out some of that precious heat. 

I also need to find a way to insulate the living area from the front cab. 

My pipes burst once, when I stayed in a hotel for a few nights. 

In Conclusion

Let me know what you all used for your insulation, why, and whether or not you like it

I have a post on my website about van insulation https://vanfocused.com/van-insulation/ and I'm looking to add to it and correct it to make sure it is accurate and up-to-date. 

I know there are things missing so if you could also give it a look over and let me know if I should update or change anything.

I appreciate you all,

Cheers.
 
I did polyiso on the floors and walls...I don't recall which thickness... The thicker and then spray insulation here and there... I did not think I would be in the cold as much as I have been so far.

I do have thick black out curtains between the cab and living area that I drop down when really cold.

My floor is pretty cold... I found some slippers, throw rugs... And often just keeping my feet up made things more tolerable.... I went and bought the "old guy" looking slippers.... Skipped being like my dad and went full on Gramps. They are great... Never wore slippers before.

I measured and about a above the floor is where it begins to warn up... I know the biggest problem is that I am getting drafts... Or breezes depending on how hot bloodied some run.

I would have taken more care to eliminate those had I anticipated colder climates more regularly.

I did buy a nice soft sightly filled bedspread.. And affixed to the wall and door paneling.

It has made it so much nicer on the inside to have warm walls to sit/sleep against... Maybe some throw rugs and some kind of fabric on the walls would make a difference... I know here at the Idaho panhandle it does.
 
desert_sailing said:
went and bought the "old guy" looking slippers.... Skipped being like my dad and went full on Gramps. They are great... Never wore slippers before.
I have been looking for warm fluffy slippers for my cold un-insulated floor, and I found some that looked extra warm, but they were pink, and had bunny ears and such.... :-/ I didn't buy them.
 
desert_sailing said:
I do have thick black out curtains between the cab and living area that I drop down when really cold.

That's what I have too but I still feel that cold air draft coming in from the cab area. I was thinking of making some black out curtains stuffed with reflectix but I've heard mixed reviews on the stuff. Do you have any thoughts on reflectix?
 
with insulation you need to go all in or it really doesnt help much for the cold. You do have to seperate the front driver compartment from the back of the van, all the cold comes in from the front windshield.
On my van the front uninsulated area is as cold as the outside temp. The back of my van is at least 25 degrees warmer even without heater. This morning outside temp was 45f, inside in the back of the van it was 68f, without heater.
The entire back of my van is insulated, 6 layers of 1/2" rtech foam on the roof, maybe 2 layers everywhere else. Very important to put foam insulation over all rear windows, also cover the rear door/side door with foam. The van has to be as airtight as possible.
Until I seperated the front of van from the back and covered over the sliding side door, the back insulated section of the van was as cold as the outside van. Too much cold air was coming in from the side door.

some temps I recorded, shows inside/outside temp around 6 am (coldest time of the day). No heater in use.
temp cold.jpg
 

Attachments

  • temp cold.jpg
    temp cold.jpg
    91.3 KB
my front curtain that separates the front from the 'house' part is double. Front side of it is a thick black-out curtain, and attached to it for the back is regular fabric. I think it will be insulating enough for drafts. I'm not going to the Arctics.
 
Without a heat source, the van will be the same temperature as the outside without the wind (picture a chest freezer). The insulation will help hold whatever heat you have in there longer, and the floor should also be done, because cold feet are the worst.
 
Here is a link to one of the insulation threads on this forum. This thread discusses insulation and glue. Hot glue seems to be the winner, I rejected 3M 90 glue due to toxic fumes. I put up polyiso XPS thick on the walls and one inch on the ceiling, also insulated the floor and covered most metal surfaces with finishes. Stays warm.
-crofter

https://vanlivingforum.com/showthread.php?tid=38458&pid=475948#pid475948
 
jonyjoe303 said:
with insulation you need to go all in or it really doesnt help much for the cold. You do have to seperate the front driver compartment from the back of the van, all the cold comes in from the front windshield.
On my van the front uninsulated area is as cold as the outside temp. The back of my van is at least 25 degrees warmer even without heater. This morning outside temp was 45f, inside in the back of the van it was 68f, without heater.
The entire back of my van is insulated, 6 layers of 1/2" rtech foam on the roof, maybe 2 layers everywhere else. Very important to put foam insulation over all rear windows, also cover the rear door/side door with foam. The van has to be as airtight as possible.
Until I seperated the front of van from the back and covered over the sliding side door, the back insulated section of the van was as cold as the outside van. Too much cold air was coming in from the side door.

some temps I recorded, shows inside/outside temp around 6 am (coldest time of the day). No heater in use.

That's great info! Thanks :)

My "living" quarters definitely stays a bit warmer than the cab but I think if I get a better insulated curtain to separate the sections it would help a ton! And my windows. I'm going to create magnetic insulated window coverings. I'll post pictures when I get around to making them!
 
Insulation in vans help a lot for noise and to feel cozy. As far as heat not a lot.
 
I do think people overthink it too much. What did you end up using?
 
It's a lot of work to properly insulate. Gonna do it? Do it all. No gaps, no exposed metal on interior side. I did 1" XPS foam board on the ceiling over 1" of pre-existing fiberglass. 1/4" XPS foam board on floor which will covered with 3/4" foam gym mat. The walls are 3.5" Rockwool because I had 3" to fill. And a pocket door I built in the bulkhead has styrofoam, because I had it laying around and it fit nice and tight in there.

Use what materials you have available, but do it all. Stay away from materials that aren't hydrophobic like fiberglass and denim. I think Reflectix and Ezcool behave differently, know when to use them where.
 
I like that advice about insulation all in, or that it does not do much good. That seems to make sense. I wonder if the floor, the sides or the roof have more impact on how cold it feels inside, one more than another? It would also seem to make good sense to have a winter set of window covers - insulated for the cold months, or is that overkill?
 
Window covers for summer or winter will definitely help, all my windows in the rear of my van are covered over with foam insulation. I concentrated on the sides and roof, the floor is only insulated in some areas. There is no overkill for foam insulation, I put layer on top of layer of foam insulation until I no longer feel heat or cold coming from that area.

This winter in my heavily insulated van was uneventful, until we started getting strong winds. Even though the outside temperature wasn't that cold upper 40's it was freezing in my van from the wind getting inside my van.
I found areas in the rear doors and also my sliding door, where air was getting in. This air going in the van was what was making the van cold.
The strong winds was forcing itself in through the smallest cracks that I didn't cover before. With no wind, I have a 20 to 25 degree difference from the inside and outside temp, with strong winds the difference drops from 5 to 10 degrees.

That to me shows how important it is to make the van as airtight as possible. If cold outside air is getting inside your van, insulation wont help much. Luckily the strong winds only lasted 3 days but it showed me I have more work to do and areas I need to fix.
 
Do people find that the interior size is a major factor in how cold it gets and how hard it is to insulate properly?
 
It definitely makes a difference in my little trailers. I try to make them with as little head room as possible to make it easier to circulate the warm air that collects up high to the floor below. In a van an insulated curtain that can be Velcroed or attached to the wall to cover doors and windows, especially the front seating area would make a major difference in my opinion.
 
Although I’m not insulating my rig with it I have been using thinsulate for quilts. It’s so light and so thin it looks like it can’t possibly do a thing.

I made my frozen old 92 year old mother a quilt out of it. She has many, many quilts she used to change out all the time and now has only taken this one off to wash. She loves it because it’s light weight but super warm. I showed her how warm by putting a small piece of it on one of her hands and a couple of layers of regular quilt batting on her other hand. She was pretty shocked. I know it’s used extensively in gloves and other winter clothing.

I think it may be a bit more costly than other insulation but it’s really nice stuff and I think it’s worth a little extra cost.

I’m currently making curtains for my sister’s casita camper and hoping I have enough thinsulate left over from quilting projects to sew it into her curtains. If anyone is in Quartzsite and would like to look at some contact me.
 

Latest posts

Top