Hope I haven't missed this in previous posts. . . . I am presently sealing the tanks and are about to place the foam in my peeler skiff, I would assume that most builders use urethane sheets/blocks. I went to Lowe's and they had no idea what I was talking about. Does anyone know of a good source in the mid-Atlantic region? Thank you.
I think most people are using sheets of the pink closed cell insulation sheeting like this stuff
http://www.homedepot.com/p/Owens-Corning-FOAMULAR-3-4-in-x-4-ft-x-8-ft-R-4-Tongue-and-Groove-Insulating-Sheathing-37L/100320340
There are various brands and thicknesses out there.
The pink stuff in the North East is now purple. I got mine at a local building supply for about $22 US for a four foot by eight foot by 2in. sheet. It took a little more than four such sheets to fill the three tanks. Lowes/Home depot charges the same $ for a two inch by 16 inch by eight foot sheet.
Thank you both. Got the pink stuff and it's now sealed in the prescribed spaces. Having a great time with the build!