[MoldAvoider]

I have purchased a van with the goal of converting it to a safe place, allowing me to travel around to good places.
Condensation is, of course, a huge issue. Because I will be sleeping there and in various climates, I need to insulate it. What I am not clear on is whether I must have a moisture barrier.
It seems to me that it would be impossible to have a totally sealed moisture barrier, especially in a structure that regularly has torque applied to it. This means there will be some condensation between the barrier and the metal side of the van. Also, dust can get in.
It I put holes in the wall / floor as "weep holes", then that allows even more mold food to come in, as well as whatever moisture is in the outside air.
It seems like what I should aim for is insulation I can remove and wash off, wash off the walls of the van, let dry, and then put the insulation back. That, of course, is a tremendous amount of work given that I'll have stuff inside the van.
I'll have one or more small electric dehumidifiers and probably desiccant-type ones, too. But they can fail.
I've searched so much online and nobody seems to think about moisture-barrier failure in a van.
I'm looking for advice!
Thanks.

 

[keeponvaning]

Welcome to the forum. There are lots of threads on insulation here. Pick the one that fits your needs the most and stop overthinking it.

 

[MoldAvoider]

Thanks. I did a bit more searching and at least found out that there already are weep holes. (I found out more, too.)
There are a lot of aspects of this "different sort of conversion" that I'll have to figure out on the fly and be flexible about. Moisture-management isn't one of them. It is simply unbelievable how just a tiny bit of mold can make me sick.

 

[RDinNHandAZ]

I have no special knowledge but a bit of thought might be a place to start.
You will not stop the condensation of moisture on the skin of the van w/o covering all the metal surfaces that are hidden with insulation. The only insulation that can do that is sprayed foam. GaryBIS had his van sprayed and you may want to contact him with a PM. In your case you need to have thin layers of the foam sprayed everywhere so the ceiling above the cab and the door covers need to come out. Condensation will not happen on the sprayed surfaces but accumulation of dust on those does have the potential of growing mold in humid places if it is not anti-Zygomycota proof. Mold doesn't need liquid water to form or grow, in fact a humidity of about 50-60% is fine for them. I don’t know if there are treatments that would be effective and compatible with the foam which I believe is polyurethane based. Insulating foams have fire retardant chemicals added and other trade secret additions as well. As I understand you have additional environmental sensitivity so you should investigate your compatibility to spayed foam. Well cured foam must be in many Austin buildings of various uses so a night in a motel that had it done, or an afternoon in a mall might show that it is ok or not. Avoid places that obviously have other environmental chemicals to have a fair test.
About removable insulation and cleaning. It would be possible by building minimally and modularly. My conversion for example can be removed in 20 minutes except the over head cabinets which would need wiring modifications and then another 10 minutes could remove them. My walls have the factory panels which can be removed but if done a few times the Christmas tree shaped plugs would need to be renewed. In this scenario insulation could be attached to the panels which would not prevent the condensation on the van but periodic inspection and removal along with an anti mold wash might give long periods between issues.
Moisture is expected by the van’s designers so a path for it’s escape is built in. The lowest panels called rocker panels act as scuppers to collect the condensate from the walls (and ceiling) and they have open drain holes to the outside. Those holes allow dust in which will surely contain the spores of mold as it is literally everywhere, including the harshest palaces on Earth There are probably a quarter-million varieties of mold (my guess) and you are probably sensitive to a few. You WILL NOT keep them all out so this is a mitigation issue not an eradication possibility. I suggest you accept that the van will have some condensate and dust and control your exposure by avoiding places that have a lot at the times of year they are moist. As an example don’t plan to visit me in SW AZ in August as the monsoons raise our humidity to 90+ for a month or so (and I will be in NH!). Places with a humidity of 30-40% humidity have few mold issues.
I would avoid using fabric-like insulation that holds moisture as it raises the vans humidity for the time it evaporates. Research the possibility of a mold proof woven insulation like Hein’s Thinsulate to see if it has any mold protection. He probably can find out if he doesn't know. Keeping the condensate as a liquid and draining it from the van as fast as possible seem to me to me a good plan.
Vinegar (which I really like) is a reasonable mold killer and believe it or not it’s smell dissipates fairly well. I’d periodically remove the insulated panels, spray vinegar from a garden sprayer everywhere, let it drain and dry, air it out and replace the panels. Initially prepping the van this way might be a good way to find out if you tolerate that and if not wash the van down to remove it.
These are some rambling thoughts. Others with mold sensitivity may know more. Julie?

 

[emat]

I have no intention to try and install a moisture barrier in my project. Thinsulate insulation, a source of dry heat during the wet months, and plenty of ventilation should take of any moisture that 'might' accumulate. I'll also treat my plywood sheets with MinWax water based oil-modified polyurethane before affixing them to the van.

 

[Hein]

Thinsulate(TM) is mold and mildew resistant. (See 3M specs below)
A breathable wall would be best to prevent moisture from being trapped.

http://www.3m.com/3M/en_US/company-...Insulation-SM600L?N=5002385+3292659035&rt=rud

 

[MoldAvoider]

Thanks for all of your feedback.

I know I can't eliminate moisture or mold spores, or mold food. I'm seeking "moisture management", meaning I have done what I can to a) prevent excess moisture from entering the van b) remove moisture via venting and dehumidifiers c) control (as best as possible) on which surfaces there will be condensation d) channel as much of the condensate as possible to the outside of the van and e) be able to clean up standing moisture, including that in on condensing surfaces, the channels, at windows, etc. There might be parts to moisture management I haven't thought of.

c, d and e are all greatly affected by moisture barrier attempts and insulation. The easiest way to handle these elements is to have bare walls, but of course I need to keep the van at livable temperatures.

It feels pretty impossible to put foam (or any insulating material) against every single piece of metal.
Also do have foams fire retardants and that is an issue for many. I don’t know how much of an issue it will be for me. I can’t go into most buildings – especially flat-roofed ones like hotels and malls – so that sort of challenge is tricky.

Does anyone know if the (factory-placed) foam behind the ribs anything close to moisture-resistant?

I have one mold-avoidant friend who has put in a “floating wood floor” which he occasionally removes to clean under. This made me think of removable insulative wall panels, made with moisture-repellant material (TPO? Thinsulate?) The panels would not be glued to the side of the van but instead somehow mounted – to the ribs? -- to make them removable – velcro? It is the “somehow mounted” that stops me in my tracks.

I need to be able to access the holes / anchor points because I won’t be “finishing” the van before I leave – I need to get out of town ASAP, which is already too many weeks away. I plan on attaching cots (when not in use) and metal shelves or metal baskets with tie-down straps and bins into the shelves with bungee cords. Simple. Ugly. Probably loud until I figure out how to pack it all better.

But if the ribs are not filled with insulation, even if I glued insulation onto the non-holes part, there is going to be a lot of outside temperature coming in. I can get a wall-mount anchor system installed over insulating panels but then I can’t remove the panels to clean.

Which reminds me – how can I find out the weight limits on the different holes / ribs / cross beams?

How would I do removable panels for the roof?

If I did go for this out-of-the-norm option I think I would use BedTread for the floor because it is removable, sound reducing and insulative. Probably doesn’t insulate well enough but if need be I can add matting on top.

Also, don’t kill mold inside a living / working space. It doesn’t like being killed. Like all living things it fights to stay alive and in the process it sends out its toxins (If it is a toxic mold). In fact, toxic molds will continue to release toxins even after the colony is “dead”. If the mold is on a porous surface, it will have sent down roots that bleach, etc. cannot reach. The colony won’t be dead. It may not be growing, but it can still send out toxins and it will grow again with new moisture. At the very least remove the moldy item from the van before attempting to remove the mold from it. … The mantra is that you cannot stop existing mold from coming back until you know the source of the moisture that feeds it and remove that source.

 

[GaryBIS]

Hi,
I am not even remotely knowledgeable about avoiding mold problems in van conversions, but, as RD said, I did do my van with polyurethane spray foam.

I'd just say that for broad panels between the ribs, the spray foam covers well and it adheres very well to the van metal skin. Nothing is going to get behind it in these areas -- not mold, not condensation, not water vapor in the air. The van skin and the foam insulation will act as a single unit in these areas.

It is unlikely that you will get condensation on the inside of the spray foam because it runs at the inside temperature of the van, which will normally be above the dew point temperature of the inside air. The dew point is the temperature at which condensation begins to form -- at temperatures above the dew point, no condensation. If you have an insulation that is permeable to air and water vapor, the warm air and water vapor will be able to reach the cold outer van skin, which may well be below the dew point temperature, and you will get condensation against the van skin. I guess, as you say, the insulation could be made removable and everything could be cleaned periodically -- this seems like a ton of work to me.

For the ribs, you could try filling them carefully with Great Stuff Pro, which is DIY polyurethane foam in a can. I did some of this on my van, and it would be a bit tedious to get every part of every rib and pillar filled with Great Stuff, I think that it could be done.

For your case, i personally don't think it would be a bad idea to run the spray foam all the way down to the floor and fill the cavities that have the drain holes. I don't think you are ever going to have enough condensation to need the drain holes.

If you would be having the foaming done by a commercial outfit, you could talk to them, tell them what you want, and see if they would commit to spraying the foam in such a way as to cover every square inch of area.

On my van, the only place I have ever seen condensation is on the windows when we have not put the insulating window plugs in place. You might consider using double pane windows, which would greatly reduce window condensation. I think that Motion Window offers double pane windows.

I have no idea if the spray polyurethane foam could be a problem for chemically sensitive people, but have never heard of it being a problem. I would think some Googling would let you know on that point.
Also don't know if polyurethane supports mold growth on it, but I think likely not -- more Googling.

I do think that in your case, spray foam might be a good solution for you that would not require all the work of removing insulation for cleaning.


It seems like someone must have tackled this problem before and found out what works. I'd post your question on all the van conversion forums (Sprinter, Transit, CheapRVLiving, ... lots of them), and see if anyone has been through this already.

We have been getting a lot of wildfire smoke this year, and it has me looking at ways to keep the air inside the house free of small smoke particles (less than 1 micron). There are filters out there that will filter sub micron particles, and these will filter out bacteria and even virus -- I'd guess they would take care of mold spore and dust. Look for MERV 16ish ratings. There are small portable units that have a filter and fan and can be placed in a space to clean the air -- maybe look into one of these?

Gary

 

[MoldAvoider]

Gary,
Thanks for your considered and detailed response. It is so good to know that there are people "out there" who are willing to help me find a solution to my problem.

There do seem to be some real health issues with polyurethane spray foam.
https://www.epa.gov/saferchoice/quick-safety-tips-spray-polyurethane-foam-users
https://www.epa.gov/saferchoice/potential-chemical-exposures-spray-polyurethane-foam#long-term

For someone like me, I wouldn't be at all surprised if the stresses applied to the van while driving in 100+ degree temps caused enough degradation to affect me.
https://polyurethane.americanchemistry.com/Resources-and-Document-Library/6936.PDF

I do need to spend more time searching in other forums. I allocate as much time as I can to van-related research but as we all know there are other parts of life that demand our time. There are others who are living on the road trying to avoid mold; I am on lists with some of them and nagging at them constantly for more information. Everyone has a different approach and not all of them work. Some do a lot to keep their van in dry climates -- running away from rain storms, for example. Others don't venture into colder areas. I'd sure like to figure out how to have more freedom than that. The fact is that they all work very hard at daily tasks. All wash their clothes by hand, for example. They wipe or wash down the insides of their vans often daily. Few have plumbing inside the van because black water tanks grow terrible (for us) biological toxins and gray water tanks can get bad, too. I don't relish the thought of removing insulation panels to clean them! I'll have more than enough to do with my time. (I will also be home-schooling my 12-year-old son!) But said son can help with removal, cleaning and re-installation.

At this point I am delusionally picturing a panel system that is attached to the inside of the ribs and roof cross-beams, attached perhaps by Velcro. (Panels being moisture impermeable). There are times when there will be condensate on the van walls and roof and condensate from the roof may drip onto the panels, so getting them properly sealed is a big issue. Condensate on the walls, if it doesn't evaporate will roll down and I'll need to clean ... what about inside the ribs? Maybe I just have to give up and constantly run away from the rain. ... But I need to try.

Also, while HEPA air filters can be quite good for removing smoke, viruses, etc., they do not remove the biological toxins created by some molds and bacteria. Both the actual molds and their toxins affect me (in different ways.) Oddly, part of the process of healing from sickness created by long-term mold exposure is that symptoms get worse with smaller exposures. (I can try to explain why if you are interested.) Getting away from as many toxins as possible is a primary way of getting out of the super-reactivity phase. This is a main reason for why I will be "vanning". The other main reason is that I don't believe I will ever be able to live a normal-ish life in my current city. I need to find a city that isn't so humid, has newer buildings that I can tolerate (for living -- if I am that lucky, shopping, doctors, etc.) and which is only a few hours' drive from a Very Clean Natural Place. This is a very frustrating, tricky, isolative, turn-your-world-upside-down "disease".

Thanks to all of you for your brain power!

 

[RDinNHandAZ]

The other way to control condensation is to vent. That has some risk for you I would guess. GaryBIS’s filter suggestion in the roof fan might be able to push air out the side windows and filter the air you pull down through the vent. We get condensation on our windows too. insulated covers are the answer.
You won’t find specifications for the hole ratings, they will hold a lot.
Hold the panels with self tapping short screws, quick and easy and there are some decorative ones.
That material between the ribs and the vans surface is adhesive, painted.

 

[GaryBIS]

Hi,

Again, I know next to nothing about this area of mold sensitivity...

But, it seems like the references on polyurethane foam talk about either 1) hazards during the application until the foam is cured, and 2) post cure conditions with very high temperatures (over 300F) that result in thermal degradation and out gassing. They mention things like welding and grinding that might generate these temperatures.

It seems like normal operation of the van should never get anywhere near these temperatures?

I do quite a bit of solar collector work. Solar collectors get about as hot as anything in the sun can get and polyurethane is routinely used in these collectors without problems. Other plastic based insulations (like polystyrene based XPS and EPS) do show serious degradation and melting at much lower temperatures (around 160F) -- polyurethane is a relatively high temperature plastic.

It seems likely to me that other insulations made from plastics would experience the same kind of thermal degradation and outgassing at the high temperatures mentioned in the references?

It just seems like removing all the paneling and then all the insulation to clean up is so arduous a task that the thought of doing it would discourage the use of the van? It certainly would for me

Again, not trying to stuff ideas down your throat -- you need to do something you are comfortable with.

Gary

 

[moose]

There are soy-based spray foams but even these are somewhat toxic. I think it's best to use a permeable insulation so that the walls can dry out. Thinsulate works in this regard if you are okay with plastic. If you used a vapor barrier you could install some flettner vents on the edges of the roof to ventilate the insulation cavity. I think a vapor retarder makes more sense than a barrier.

One idea I had was to use a one-way membrane which would only allow moisture to escape to the interior but not to the van skin.

Maybe have a quick consultation with the lady from mychemicalfreehouse.net. She works with people who have MCS and mold sensitivities.

 

[KNDLKSTMS]

I remember back in High School how the back windows of the car would collect condensate on the weekends . Even now after a 6 hour snooze the windows "collect". I would say a dehumidifier is your best bet . Look at an athlete on a cool day , steam pours off people. Sleeping bags get damp and need to breath.
Attach your chosen insulation to the interior "finish" panels , remove a few fasteners and off come the panels exposing the van skin for cleaning . Go modular , main loads to the floor , sides for support . Good luck .

 

[Hein]

If you want removable insulation then Thinsulate(TM) AU4002-5 would be ideal because it has scrim on both sides. We made a hanging 'blanket' that we use in our shop for noise control. We added punch eyes along one edge and hang it from hooks in the ceiling. This would be great on the back/front of a cargo partition as well.

 

[Julie Rehmeyer]

Hi MoldAvoider,

Sorry to be weighing in a bit late on this. I started out planning to do spray foam, and then I got a bit worried about the failures with it. I would have gone that direction if I could have found someone with successful experience doing it, but I couldn't, and I desperately needed to get out of town. So I did a combination of rigid and spray foam. That's what Erik Johnson did and he hasn't had problems even while living in Reno, which has problems with toxic molds. Sara Riley Mattson also used rigid foam -- no spray foam. I assume you've read Camp Like a Girl, right? Hers is theoretically removable, though it would be quite a pain to do so.

 

[RDinNHandAZ]

I remember back in High School how the back windows of the car would collect condensate on the weekends . Even now after a 6 hour snooze the windows “collect".

My girlfriend and I seldom spent time enough there to notice the condensation. I wouldn’t be surprised if there was some. Her name wasn’t “Little Susie” and we did have a curfew. 6 hours- you lucky person!

 

[MoldAvoider]

Hi Julie:
Yes, I've read Sara's book. From what she says, it would be far more than a pain to remove the roof insulation! Erik hadn't responded to my tag about what he uses, but I know his floor is removable so that he can wash under it. I wasn't aware he uses any foam. (The last thing I've seen him write on the subject is "Highly advise NO CATALYTIC FOAM. Very bad news for MCSers." I don't know which insulative foams are catalytic.
What I need to find out is if she, Ana, Erik, you and others unknown are having / have had any condensation problems. It seems that Sara and Ana are doing what they can to avoid being in humid environments. I guess winter will reveal more data, but I really, really don't want to wait that long.
My van doesn't seem to be progressing in its off-gassing at all (left open in 100+ degree temps for 4 days now, low humidity outside.) 1/2 of the bed was repainted last week and I had no reaction from it at all; I never did smell it either. So whatever it is that that is already in the van is bad enough that I am quite reluctant to add more.
Meanwhile I'm taking off the panels and I see clear signs of water running down the back of them and dried-out gunk in the cross bars. I'll make another post asking about that.

 

[GaryBIS]

Hi,
I'd guess that catalytic means foams that use a part A and part B that combine in the nozzle to make the foam. One of the two parts is a catalyst so the foam cures quickly.

So, that would include polyurethane foam as sprayed by commercial outfits or in the DIY two bottle kits like I used.

I'd do a little more looking to verify that foams that use a catalyst are a problem -- seems odd in that this would include foams with very widely differing composistions?

Gary

 

[MoldAvoider]

I asked Erik (the source of the assertion) "would this be all catalytic foams? Does that mean it is the catalyzing agent that is most risky?" and his answer is "Yes. Takes forever to stop offgassing." His knowledge in this matter is based largely on decades of being a mold avoider and working with mold avoiders (many of whom develop MCS in the process.)

 

[MoldAvoider]

Is Hein around? I'm hoping to get some Thinsulate samples and have tried sending him a public message and a private message but haven't heard from him.