Floor Buildup Help

Am working on a build-out of my 2015 144 low roof - I'm 5'11" w/o shoes - so I'd like to maintain as low a profile floor as I can. Rather than hijack a similar thread, I started this one.

I don't have a factory floor (gutted a previous build). As I've gotten older, I prefer to keep things quite a long periods of white noise are fatiguing. The following technique was employed in my Jeep to much success. It works far better with noise & insulation than Dynapad and is far thinner.

I'll be implementing the typical 3-level noise reduction technique:
1)resonance damping - butyl rubber & alum -
2)vibration isolation - foam
3)weight - MLV

Here is my idea for the floor:
Butyl Rubber/50-80milAluminum
Something to fill in the ribs
157mil (1/6") thick NOICO Foam insulation pad
MLV - 1#/sqft - 1/8" thick
Insulation of some sort (WHAT THICKNESS?)
1/2" ply
Floor Covering (Vinyl or rubber coin)

Van will be used all over North America as a mobile office & adventure van - it will need to handle desert heat and frigid northern latitudes...

Comments on the above buildup? ... what thickness of insulation? Was thinking 1/2", but then my floor would be >1" thick...

I don't think you need the CLD on the floor. The floor is ribbed and doesn't really resonate. 3/8" mini cell (x-linked polyethylene) works good to fill in the ribs. It also works good for the insulation layer. You can buy it from foambymail.com.

Could you elaborate on your floor for me? What did you use for adhesives/attachment for each layer? I'm planning my floor now and am currently researching the many options. I'd love to hear what your plan is and how its worked out, if you've completed it yet.
Thanks!

I used 1/2" polyisocyanurate sheet insulation from Lowe's. I don't see how going thinner than that would have a lot of value.

To go to Kristen's question also, my Sprinter has the stock floor, which Sportsmobile saw fit to glue down to the sheetmetal floor, then the polyiso, then 1/2" plywood (which is screwed into the sheetmetal through the other layers using self-drilling sheetmetal screws on about 12" centers) then roll vinyl flooring.