pictures of my insulated spray foam from previous owner van.

 

YIPES !
I wonder if that would be as much of a problem in Ca. ?

 

Well the foam holds it together after the metal rusts. Hot sun on metal will make condensation between the foam and metal also

 

Wow---that's just down right U-G-L-Y---what a shame. Then again we didn't know then what this would cause or create but seemed like a wonderful idea.

The problem Skip's showing us isn't geographically significant---its just a chemical reaction between the foam components and the sheet metal.

 

gotcha

 

i never thought of chemical reaction i guess that would be like likely also.

 

I started googling msds sheets for expanding foams
I wonder if all are corrosive ?

 

I thought that a properly painted(or coated) surface would keep it from condensating, which would allow me to out the spray foam in there but this would have to be tested. I don't think it is as much the spray foam(because it is used on housing applications which are going to be steel sometimes. I think it is more the condensation getting trapped.

The more I think about it the more I like the fiberglass insulation and insulation liner better. It can be removed rather easily if the paneling/wood is put on in such a fashion is can be removed too, and it has a better r value too. If I coat it with POR15 first, that should prevent it from condensating if it is applied properly(I would think, I'll have to do some more research).

I'm thinking I'm going to do it this way

Sheet metal
POR15
Fiberglass/Insulation Liner
1"x2" wood "ribs"(If I can't find a good way to bolt the plywood directly)
Plywood
Lamina

I'm going to see if there is a way I could I can use bolts instead of screws to hold the plywood to the van. I don't know my options very well, but hopefully I can make one of the following work(drill hole in plywood, use bolt/washer to hold in place):

drill/tap holes in the sheet metal ribs,
Tee nuts for sheet metal(I don't have welding equipment otherwise I would weld nuts on the opposing side of the ribs)
Bolt with threaded thru hole(not sure if this is a thing) in the rib
Insert bolt in rib so the threaded part is pointing towards the center of the cargo area, bolt on other side of rib, put plywood on and secure with bolt

I also need to investigate how to bolt thru the flooring properly to secure Pitbull trailer restraint system for the motorcycle, probably have to run some metal under the van to spread the force the bike would apply on the bolts so they don't just rip out.

 

I think as long as the fibers are contained , all is good with it.

 

I still wonder about the foam..the new stuff they use in homes seems to be differant and not trap moisture against the surface like the store bought stuff.
What about using a spray undercoat first??

 

Stop the madness guys! (Last several posts are running a bit off the trail on this.......let me repeat a few things..........but first:

The spray foam isn't corrosive by its nature, at least for the materials its designed to work with; construction materials like wood, cement blocks etc etc. Sometimes that which works perfectly in one trade will be a complete failure in another. A lot of automotive-related materials in general are significantly from something that appears to be similar, for example auto upholstery & carpeting. One can't visit Jo-Ann fabrics for cloth and redo their interior, same with household carpet. Because their end use is so very different even though they seem to be the same thing they're not.

So onto the first steps in insulating a van:

-There's no need or benefit going crazy on insulating our vans---its really simple, trust me. In the overall bigger picture we only need to cover the bare inside walls and floors with something, anything that will intercept airborne moisture, aka "humidity". We can't control or 100% exclude humidity because there simply too many places it will creep in. We need to manage it instead.

-Using something like the radiant barrier insulation (RBI) I suggest is it doesn't encourage humidity to condense on the inner sheet metal--plain and simple. If just a single layer were applied to the larger interior areas (including ceilings) you'd never see condensation on those areas. Not the visible parts, not the metal between the insulation and the sheet metal.

-Anyone who has driven a bone stock van with just the OEM floor padding and bare walls has almost certainly experienced the floor mats being very wet after sitting over night during high humidity days/nights. When I've had just the walls and ceilings covered with RBI) I've NEVER had this happen again.

IF there is existing surface rust already formed under the OEM padded mats that needs to be addressed. If not simply clean the interior metal, use RBI (single or double layer) on the walls/ceilings and nothing more than 3/4" plywood for the floor---these simple steps will assure your van is about as trapped humidity free as it will ever get.

It really is this simple, anything more complex is wasting time, material and money.

 

they are saying it's a chemical reaction not a water condensation issue.
I think your undercoating idea is a good one but I just don't have an answer
I looked up the msds sheets for chemical reactants and didn't find anything definitive

 

The typical "cheap" undercoating would be okay especially when using it inside the van. Personally something like Rhino liner or Line-X would be better. Monstaliner also a great product.

However those are somewhat expensive steps along with extra labor not really necessary. I'm not trying to push my method however its the same in terms of function regarding managing condensation.

Think of it like this---humidity that migrates inside the van will condense on any surface to the inside of the interior---its unstoppable. What we need to do is make the first surface it does condense upon NOT the body sheet metal.

Even if we left the interior body and ceilings uncovered with anything yet covered them both with something non-absorbent we're giving the humidity something else to collect upon. As such that material would be "sacrificed" yet unaffected----that's what we're trying to achieve.

Keeping that in mind just don't use anything that will absorb moisture and we should be good to go---for a long time!

 

Got it. No using wadded up old newsprint!
I do like the idea of stuffing all the voids with fiberglass.

 

crap.....
sounds like the way to go......