[poundsand]

Read do many build threads on so many forums I feel my eyes are going to pop out. :-D

Want to confirm a few things as generally accepted wisdom:
- polyiso is the go to choice on floors
- polyiso or thinsulate win for ceilings
- Walls... Seem more of a crapshoot, with most on this forum preferring thinsulate

A few questions on sound deadening:
- anyone add sound deadening in the cabin area - floors, doors, and ceiling? Don't seem to see any mention of it.
- mass loaded vinyl on the floor in cargo area - don't see anyone doing it? Not thought to be worth it?

 

[Ziggy Stardog]

Insulation is a source of constant debate. Polyiso and Thinsulate are the front-runnings as you note. I don't recall too many folks using anything but polyiso under their floors.

There are many sound deadening threads with similar debates and even less consensus. Thinsulate absorbs sound as well which further muddies the waters. Personally, I'm doing a modicum of Noico sound deadening as cheap insurance. If it doesn't actually do anything to an insulated van... well at least it will keep the polar bears away.

My advice would be to make friends with the forum search function, go through the threads and draw your own conclusions.

 

[keeponvaning]

If you are covering up your insulation then sound deadening is somewhat (a huge) waste of time & money. Everyone runs out and adds sound deadening first and says "Wow my van is so quiet now!" Then they add the insulation and wall covering and... guess what? It's still so quiet

Of course, others would differ - particularly if they have a vested interest in selling sound deadening, but I digress

 

[JohnnyRambles]

I'm currently working on (re)insulating my 159" van. I purchased the van used and it was already built out and insulated with fiberglass batting. To open up some wasted space and with worries about moisture retention I decided to redo it from the ground up. So far I've used 3/4" EPS foam on the floor covered by 3/4" plywood and the stock rubber mat. On the walls and in the doors I've added 80ml Fatmat sound deadening mat which covered about 1/3-1/2 of the flat surface areas (This made a big difference and eliminated a lot of the "tin" sounding especially in the doors.). Next I'll be adding sheets of EPS foam in varying thicknesses from 1/2-2" depending on the location. I have a local source for free EPS scraps and will be using that to fill all the hard to reach voids in the body. Then I'll be taping all the seams, adding a layer of Reflectix over everything, taping the seams again and covering in with 1/4" plywood.

I will say that when the van was insulated solely with fiberglass batting and plywood it was very quiet. The downside was it took up a lot of space and I'll be regaining about 5" of with and have the same/higher R value using EPS foam instead.

 

[Ziggy Stardog]

If you are covering up your insulation then sound deadening is somewhat (a huge) waste of time & money.

Which is why I concentrated on the floor of the cab, and the leftovers go to trouble areas like the wheelwells etc. if it was much more than $60 I probably wouldn't have bothered.

The trouble is these are both a play on our fears of the unknown. In uncertainty, there's opportunity and profit. Probably one of those Ferengi Rules of Acquisition. There's no truly objective studies of relative benefits of any of this stuff.

No snakes, no snake oil or polar bear charms for that matter.