97 E350 Cargo 5.4, cab divider cage

I am planning to "dual insulate" my van, I want to insulate the cage and put plexiglass over the mesh of the cage so I can still see a bit out of the rearview mirror. The reason for this is to keep the a/c unit from having to cool the entire van and be more efficient. Then I plan on insulating the cargo area to keep my craft show supplies from getting too hot.

Current plans include:
Foamboard on walls and cage metal
Plexiglass on mesh
Fill in gaps around cage with foamboard
Make Reflectix covers for all windows and windshield for when it's parked or when camping
UV tint all windows (eventually)
3/4" plywood floor with industrial carpet on top

There are a few things I cannot seem to get a solid answer for. First, I was reading about "heat transfer areas" caused by the ribs in the walls and ceiling. Some people say to fill in the beams with spray foam. Others say never to use spray foam because it can cause major rust issues. As this '97 has damn near no rust that I can find, I would like to keep it that way. Has anyone filled the ribs with anything, and what works best?

Also, one subject that keeps coming up is condensation. I haven't noticed any, but then I haven't had the van long so I don't know how it acts in colder weather. I read one post where the ceiling was painted and never got wet afterwards. I was thinking of painting the roof with one of those reflective insulating coats, but this article was referring to painting the inside. However, I can't find that article again and I don't know what paint they used. The only other option I can think of is foam board on the ceiling and covering that with some kind of paneling. However, if I can get decent insulation and some noise reduction with something like bedliner or undercoating and just painting everything that would be great.

Apparently the previous owners had issues with the roof rattling, because there are a few parts where there is newspaper folded and stuffed in between the ribs and ceiling. If I can use spray foam there it should solve the issue, if not I read that was "glued" with silicone from the factory. I was thinking about filling the gaps with weatherstrip foam and caulking it in there with silicone. I've searched the forums but never found anything about a solution to that.

Last, I was thinking of installing a roof vent in the rear. I saw a solar powered one with a fan a while back but the cfm was pretty low on it. I also don't want leaking issues or having to deal with constantly opening and closing a cover. This van will mainly be used only on weekends, so it will be sitting uncovered for most of the time and I am trying to keep the interior as cool and dry as possible. Any advice would be greatly appreciated.

 

I can only comment on my experience.
I had a older extended Ford van. It was a window van too. So it had a lot of surface that the sun could use to heat the inside of the van. The roof had a factory headliner that seemed to keep the sun on the roof from heating up the van but the windows were the issue. I used a roll of the Reflex silver colored "bubble wrap" type insulation to cover the windows. That worked quite well. I kept the panels in place all of the time as I had towing mirrors so I didn't even use the rearview mirror. When the van was parked I had panels of the Reflex to cover the windshield and side windows of the front doors. It kept the van much cooler than it would have otherwise.

The foam issue is less likely to cause any rust if you spray some paint or other coating on the surface before adding the foam.

 

Saw this video, really surprised me that he recommends NO insulation if you're primarily just wanting to keep heat out of the van and not actively cooling it with a/c.


Still going to do the Refletix and insulate the cab for sure. Plus I'd like to coat the roof because of the tendency for the roof and drip rails to rust. I already need to fix/replace the rear door seals.

I'm very lucky the previous owners kept this van in a garage and ripped out the factory rubber mat, in the cargo area there is no interior rust, even on the floor. When I change the seats I'm going to rip out that rubber mat, inspect the floor, and I may just go with bedliner or POR15 if I find rust.

 

Unless water got on the floor and seeped past the mat somehow you should not find much or any rust. My van was nearly 30 years old and had very little rust and none inside. It was almost never driven in winter and spent it's whole live in the Chicago area. As far as I know the owner who bought my van only uses it in the summer time too.

 

On several forums I've discussed insulating a bare cargo van, nearly every time my experience has been ignored or "discussed" so I'm done giving advice however I will speak to two things you raise Txironhead; condensation and spray foam.

Condensation does occur in the bare cargo vans both on the exterior and interior sheet metal surfaces---logically this makes perfect sense because the outside air contacts those surfaces first. High humidity and dropping temperatures causes any moisture-laden air to quickly loose or deposit that moisture on the first surface it contacts. The bare cargo vans see this very clearly---stepping inside a bare cargo van first thing in the morning you'll find the bare steel walls and rubber floor covering appearing quite moist.

ON the surface isn't a problem as the condensation tends to evaporate away HOWEVER any absorbent material inside the van----like the padding under the factory floor covers or mats---will collect and hold moisture, never letting it evaporate away. You'll see how this is highly problematic in older vans where the floor rusts away terribly, completely out of sight until the mat(s) are removed or your foot falls through a rust hole.

Removing the factory-type mats or any other absorbent material from direct contact with interior body panels is a great way to nearly eliminate this as a problem. Using plywood flooring in the rear cargo area is great--I've done that on 4 different vans so far--no floor rust. The plywood spans the floor ribs leaving air spaces where moisture is free to come AND go. Once the plywood is in place the factory mat, once thoroughly dried can be reused or carpeting applied without danger of rust formation.

Same concept with the side walls and ceiling---I use a foil & PVC sandwisch radiant barrier insulation where the foil is glued to the sheet metal 100% of its surface. Since the PVC side is facing the interior IF moisture contacts it there is no absorption, the metal is somewhat protected as its simply not exposed to the moisture-laden air. No this material has little to no R-value but it does add a bit of sound deadening and prevents moisture from laying against the body panels.

There's no huge gains made insulating the outer most metal body ribs, those where most often interior paneling is attached. If they're covered with panels moisture won't contact them, the R-value slightly higher since the paneling is basically a thermal break.

Spray foam is to be avoided UNLESS you're using one of the expensive products exclusively formulated for automotive uses. The typical home construction products are NOT designed to be directly applied to sheet metal. Additionally when used incorrectly they can expand enough to deform the cavities where they're installed, like the tiny spaces inside the side wall and roof ribs.

I will use UNFACED fiberglass insulation in the lower cavities and between the radiant barrier insulation and interior paneling if that's applied.

The "system" I describe keeps the van heat loss or gain much much lower than one might imagine. I also fill the rear doors with unfaced fiberglass insulation which is then covered with any existing or DIY panels over the door cavities. This slightly increases the overall R-value of the complete van and helps reduce road noise too.

So that's all I know---hope this helps.

 

I had good results insulating the roof of my 2003 with 1/2" foil faced polyiso and reflectix window coverings in my adventure van.
The ribs on my van are 1/2 inch so the insulation filled the voids perfectly.
I didn't insulate the ribs since they are a dead air space and don't transfer much heat compared to the bare metal roof.
You can see some of the insulation around the fan in the second picture on post 11 of this thread: https://www.ford-trucks.com/forums/1...read-pics.html
The Fan-tastic vent fan was the single best addition to keep the van cool, it has amazing airflow.