So insulating/sound deading is on my to do list and I have been a bit of reading. It seems like people have had good luck with using fiberglass insulation for the wall cavities etc. My biggest concern with using the fiberglass insulation is moisture retention. Has this been an issue for any that have used it? I would worry that it would retain moisture and contribute to rust. Thanks

 

Yup, fiber glass insulation can soak up & hold moisture from leaks or condensation. But my "biggest concern" with fiber glass was all the itchy glistening dust that gets loose from it.

Also didn't like the typical, space consuming, fiber glass insulation installations. So many fill all the space between the van's ribs & panel over the tops of ribs, decreasing interior space quite significantly.

Instead decided to use 1" semi rigid foam sheets for roof & soft/flexible 1" closed cell foam for walls. But I made upholstery panels that fit between wall ribs & got roll of felt backed vinyl material. Used hard Masonite to back roof panels, covering/holding foam. Installed w/combo of contact cement & screws. Gained a few critical inches of width that was greatly appreciated.

 

I got rid of almost all fiberglass.

The first reason is the one you mentioned.
It has been soaking with water.
Fortunately the sheet metals didn't rust, but the wooden door panels were all rotted from inside.

The second reason is it doesn't insulate that good.
It didn't make a big difference if I had it in or not.

I got insulating boards made of polyethylene foam.
It is designed to insulate RVs
So it is for insulating sound, temperature and moisture

I used carpet glue to bring them on.
One other advancement is, that when it is glued all-over a sheet metal, it reduces the vibes that causes the drone in the interior.

 

Cobra-Kai is onto something here, building on his ideas..........

Moisture retention inside almost any bare metal interior van is a huge issue. If you live in a three or four season area where humidity, rain, snow are present just look under the OEM rubber mats. Those with the standard backing or padding material are typically soaked almost all the way through even after a month or more of dry weather. Bought a new-to-me '03 and one week before picking it up had the PO flip the mat over to let it dry out. Still wet and after removing it completely took another two weeks for it to fully dry. Anyway.........

Twice before I've used a radiant barrier type "bubble wrap" insulation on the bare walls and ceiling. This has one PVC face, one aluminum face with the bubble wrap material sandwiched between. 3M's 08088 spray glue attached it all to the van's interior. This single step greatly reduces the drum like droning so much vibrating sheet metal causes while driving.

There is also a noticeable reduction in heat transfer, summer time interior surface temps a full 20* lower than the same exterior surface. Winter temp differences not so great but it does warm up and maintain the interior temps more easily

The lower cavities of the body below the center horizontal rib and doors were filled with Johns-Manville unfaced fiberglass insulation, the white stuff. Actually the pink stuff by Owens-Corning works just as well but the trick here is to use the unfaced variety.

(for the finished walls I used a high quality .090" ABS material similar to the pebble textured stuff found in commercial bathrooms. I didn't seek to seal everything up too severely, wanting the somewhat free exchange of air.)

Moisture trapping was a huge concern for me too using the above-described method. As luck goes a full five years later after my first installation I had occasion to remove some of this material and everything was bone dry; insulation and the filled caviites too--nothing to suggest moisture had ever been present let alone retained for any length of time. Keep in mind this van had been sitting for long periods of time which tends to allow moisture to accumulate---no normal heat from driving or fresh air exchanges the root cause there.

You'll find the biggest sound reduction comes from a plywood floor, no less than 1/2" however I use 3/4" covered then with a heavy commercial grade carpet. I used an Interface brand: https://www.interfaceflor.com/Defaul...=2&Sub=1&Ter=3

The claimed absolute best insulating method for the side walls is a 1" or 2" rigid foam captured between the exterior walls and built out interior wall. Unfortunately this doesn't easily conform to our van's interiors and you tend to lose inside space this way. Its huge upside is there are no sealed or filled cavities inside if you need that piece of mind.

So that's what I know---take it for what its worth.

BTW hope to see photos of your project as it proceeds---some here might have other suggestions to share!

 

Thanks for the info. Along with the moisture retention in the walls I had thought about the dust thing. The dust could be prevented by adding a layer of plastic, but then it seals in the moisture. I read somewhere where a person used the insulation to stuff in the cavities but put it in plastic bags first. This would eliminate the moisture and dust issue, but did't know how it would effect the sound deading ability of the product.

I did read allot about adding a plywood floor to add a layer....still debating on this one. My stock carpet is in great shape and I don't know if it could be used along with the stock floor trim pieces if I added that much thickness. There is carpet pad for sale (the higher end stuff) that is made from a material that does not absorb water. I was thinking about a layer or two of this on the floor/ceiling. Also going to use it to wrap the outside of the doghouse and then cover it with carpet.

Keep the ideas coming...the more the better. I am in the info gathering phase of the project.

 

Are you starting with a bare cargo van or something like a Club Wagon with the full interior? That info would be highly beneficial to those of us trying to help.

As for dust once you have the walls covered and some sort of floor it won't be an issue. At least not to any great extent, nothing more than typical vehicle accumulation if not vacuumed occasionally Plastic encased fiberglass would only mimic the floor pad issue I mentioned earlier.

Whether you use plywood or not I'll repeat ANY carpet/pad which is resilient WILL absorb moisture and trap it against whatever it lays against. Here's something I did last year, read and look at the "before" photos if nothing else: https://www.ford-trucks.com/forums/1...-por-15-a.html

It can be argued plywood can/does also absorb/trap moisture however when applied correctly there are air spaces under it which allows free air movement. Since there is moving air (albeit a small amount) condensation doesn't collect on the floor's painted metal surfaces and into the resilient padding.

Its certainly your call and I'm trying to save you aggravation down the road if this is to be a keeper van.

 

Years ago J.C. Whitney used to carry custom formed foam van floor pads. These flexible, dense, closed cell foam sheets fit the floor ribs very well, leveling it & filling all the valleys. Wonder if anyone has seen a source for these recently?

Converted the FORD cargo van into a camper & wanted to retain maximum height & minimum weight. Didn't plan to haul rough cargo in passenger area & got away with using 1/4 hard Masonite under carpet. The foam supported it very well. Had cargo area at rear, under removable bed.

For extra sound deadening, w/o sacrificing interior height, & to help fight Tin Worms, I also invested heavily in undercoating. The floor got cleaned, repainted & sealed from above, before laying in the flooring, but most of the work was underneath. Used a Steam Jenny to blast the floor/chassis clean, dealt w/minimal rust, resealed seams & then carefully used a case of spray undercoat to build up a thick layer of the rubberized goo, on every surface I could get to underneath. Also used cans of brush on undercoating for areas that defied spray cans.

Found this material was surprisingly effective at sound deadening, as I did it before body work, painting & starting the interior.

 

The van is an '88 E250 ClubWagon 7.3 IDI. Full interior. I am wanting to remove the carpet and side panels, add the insulation and then put them back in. Mostly I am looking for sound deadening. It is a vehicle that I plan on keeping for an extended period of time and want to do it right. Currently I am putting together different ideas and weighing the pros and cons of each.

 

That certainly changes things, limiting your options. Afraid you're gonna need to pull some panels to see what you've got.

Some high end "Full interior" versions got optional Insulation Package. Feature became Standard on Chateau. The ones I've driven have been very quiet for a truck.

Believe there may have been 3 levels of "sound deadening insulation" over the years. The Optional insulation is die cut to fit & may be worth trying to transfer & salvage, or even double up.

 

Ah, well this certainly changes everything. Knowing this up front could have saved you a lot of reading our ideas!

The windows alone will allow a certain amount of noise and there's not a lot to do about that. I'm assuming you want to keep them uncovered.

The roof should be covered with a formed headliner behind which there is little room to add anything. Most fully fitted Club Wagons with rear heat & A/C sometimes are ducted into the headliner and vented downward to the passengers.

Side walls have a similar insulation material to the floor and not a lot of room behind those panels to add much more. Using an adhesive sound deadening material, the bubble wrap radiant barrier stuff of the heavy bed liner material directly to the exterior sheet metal would add a bit but not a lot really.

Find a suitable method of choice to treat the bare floor under the factory carpeting---that might make a big difference. I've never driven or ridden in a diesel Club Wagon but have to wonder if the engine noise can be tamed or even significantly reduced?

That's all I've got---hope you land upon something that works to your goals!

 

So went and examined a little closer (took some pics). My rear AC isn't ducted in the ceiling. Its a long unit along the drivers side that has 4 vents that exit under the drivers side windows. The ceiling does appear to have some type of foam cushion in between the rails, but it feels like there is allot of empty space between it and the ceiling. I pulled a couple of door panels and found this. It looks like there was some thin insulation attached at some point, but it has fallen down and deteriorated. I replaced my window motor in the front door and it had none.



I then pulled a back panel out to see. Same thin insulation that had fallen down. There is still tons of space....enough to fit r-13 easy. Here are some pics.



To try and cut down on the engine noise I think I am going to add a layer to the outside of the doghouse and then see what I can do about insulating the firewall.

 

He's got an '88 Club Wagon. That has an entirely different interior. That should certainly change things even more.

My old '85 Dent Side Club Wagon XLT had Hard Board headliner sections, spliced w/trim strips at roof ribs. No AC ducted into the headliner, just some outlets below side windows.

 

Okay---photos are always a great idea---thanks for posting them!

The stuff behind your side panels and inside the doors most likely is also above the ceiling trim too. As you notice its lost it's adhesion and deteriorated to the point its pretty much worthless now.

Stuffing the R13 into the sides would be a great improvement. For those areas and the doors my suggestion for radiant barrier glued to the sheet metal then unfaced fiberglass bats would be just the ticket. Naturally you'll clean the existing stuff out, vacumming as deep into the lower sides as you can get, door a lot easier.

Either way you go be sure to insulate behind the heater box and the ducting as it heads toward the front seats. Its a small step that will make you heating & A/C ever so slightly more efficient. Splitting the R13 is easy enough, think of filling a wall cavity with horizontal wiring and how you'd best get around it without lowering the R value by compressing it in those areas.

Since you don't have the ducted ceiling that will be a bit easier. Hard to tell exactly what's under the headliner now but most likely the same as you've found down below. If removing the headliner completely and you find its not deep enough for the R13 I'd first apply the radiant barrier to the roof sheet metal, perhaps two layers, both between the ribs and leaving their flat surfaces bare to accept the headliner.

If the radiant barrier for the ceiling doesn't appeal to you pulling the R13 apart reducing its thickness would be a good alternative. Keeping it in place while re-installing the headliner would be a minor issue, perhaps use a spray adhesive to hold it in place just long enough to fit it all back together.

Honestly the biggest chore here is getting all the interior panels and headliner out and back in---tons of clips, fasteners and other aggravations await you!

Post up some photos of your progress if you think of it. Hope this goes easy and works out great!

 

I also own a C-3 (68-82) Corvette and this is a frequent topic on "Corvette Forum" because of the heat that invades the interior. The best solution has been foil faced foam "blankets"...I forget the brand name. There was a thread awhile back that compared different brands and prices and performance. You may want to investigate that solution.

 

Rick1025 do you have any links or product names or part numbers to your findings?