Brian fits the styrene skin first and back fills behind it with P38 before fitting deck supports, then the deck then a styrene skin on the deck.
This worked great for me on the Portgarth but a ply deck was a mistake as no matter how careful water will affect it at some time for the worse.
I'm working in a vey different way with this by doing first deck supports then deck then bulwark skin and not an ounce of resin or a wiff of P38.
Much less materials used and far cheaper.
I cut the Paxolin outdoors so the smell is blown away along with any dust
1200x1200 sheet of 6mm is only £53 delivered