Insulate shuttle bus roof necessary?

[TripleBeamDream]

In my 2012 shuttle bus I’m working on gutting it now.

There is a fiberglass roof, 1.5” of fiberglass laminated cardboard, then another 1/8” inch of fiberglass for the ceiling.
. There’s 3 or 4 layers of fiberglass on my ceiling for about 2.5” of materials.

My ceiling is only about 5’10”. I really don’t want to take anymore precious head room.

I know fiberglass makes for great insulation. My question is would anything I replace it with be inferior to what is in there now?

[Jolly Roger bus 223]

since you are gutting.
in my opinion?
i would lose the lower ceiling and the fibreglass insulation mark and pull the wiring out run conduit for the wiring in the upper ceiling where the fibreglass insulation was and after the conduit and wire is done then spray foam it and finish the ceiling back to the curved section and gain that head room back.
especially i you want to insulate the floor.
just a quick opinion and alot more thought about means and methods would need to go into it?

[TripleBeamDream]

Thanks for the tips Jolly Roger. Do you have experience with spray foam? I’m decently handy and very ambitious. I feel like with a good amount of research I would be confident trying it myself. However I’m wondering if subcontracting that part out is only way to go.

[Jolly Roger bus 223]

cant think of the brand they buy but there are several on that have bought DIY kits big enough for there buses and had good success with it.
you should be able to go into the search function and look up DIY spray foam and those threads will pop up but if not some of them should see this and expect more opinions and advice.
or just start a thread asking about the DIY spray foam
some have done it thereselves and some have paid to have it done.