My insulation theory, take a look.

jesseannie wrote:
I think your theory sounds good. I have filled/sprayed poly-urethane insulation a few times and my first question is why did the company that did the upper portions not want to do the lower?
The second concern is having loose material in the cavity I think will be a problem. Unless it is fixed in place I think it will float and move making it difficult to get the cavity full. The material that you will pour in is probably going to be pretty thick and it may not fill around the loose pieces as well as you think.
Remember to get an R-value of 6 you only need an inch of material. You don't need to fill some of those huge cavities.
What are you going to use as a finish on the lower walls? Can you build out a little and incorporate a rigid urethane board in the "furring" this might be an advantage when running electrical or plumbing not to have it encapsulated in permanent foam??
Good luck I love working out tough application problems like this.

jesseannie

They didn't want to do the bottom part for two reasons, the first one being that they stopped insulation van's if what they are spraying it on is metal, because of the high temperature vs the metal panels = warping like I mentioned earlier, so I told them to just do the ceiling and upper walls and they agreed. The other reason is that they didn't have access to the outer panel because of the inner panel, they have to be 16" away from what they are spraying, they can't just insert there nozzle in a whole and press the button, it just doesn't work that way.

The other question you had about the loose material, I'm not so sure anymore, initially I was thinking breaking the rigid insulation into small pieces maybe 2"x2" or smaller, and I filling the void until they're stuck there and they can't move. but if I do that I wont be able to pour it on the bottom... the mixed liquid is going to hit all those pieces and probably won't make it to the bottom, leaving some air space here and there...
Maybe I could insert some pieces manually from the top after pouring the liquid?

I will have to drill 2" holes with my hole-saw on the inner panels here and there, if you look at the inside of a Ford van those holes are random and in some areas there are none.

I don't know how to limit the pouring to 1" of insulation on the outer panel, the ways I see it, I have to fill the whole thing :-/
Do you have an idea?
I won't be running any wires or pipes in there anyways.