For the roof and smaller spaces where the Insulation Board is too thick and would subsequently reduce living space etc. I decided to go thinner. I bought a roll of 1/4" insulation and cut to fit, using spray adhesive to stick it to the fiberglass roof.
You can see the inset gaps here
For some of the last awkward spaces between boards in the roof I added strips of Insulation Board/ spray foamed them in. Once this insulation has been trimmed I will use more of the Roll Insulation on the remaining exposed areas you see (green)
Of the Insulation Board that was used in the van, this purple board has the highest R Value and is the sturdiest. I used the last of the purple board in the rear of the van, where the bed will be. I spray foamed a line in all the floor channels and pressed the boards down while it set. Then I locked in all the edges and gaps with spray foam. Next I will put a 1/4" wood sheet on top of this as it will become storage space under the bed.
