Insulating the hull questions.

[ebb]

Hey Kent,
Glad you're still here!
Finally got back to the boat and happen to be gluing
vinyl coated polyester fabric onto the ensolite I pasted into the boat just about everywhere above the waterline years ago.
I think Armacell is a new owner of the name ensolite and is trying to obsolete the old with formula changes probably and name recognition. Ensolite has been around forever.

The ensolite I have is light tan and has a wrinkled 'skin' like surface on one side* - not really skin but more like the smooth mold surface it was extruded out of. That's the exposed side I'm covering. Imco it's not a good surface to keep clean, even tho the closecell sponge won't absorb liquids. The opposite side cut surface has a definite cut cell texture.
Like the light color. Notice in the Armacell lit a lot of their ensolite foam is black. Ensolite has a soft feel even tho it is firm. Tho firm, it's formable against the concave curve of the hull. Light color allows pencil marks and notes to be written on it. Don't think I'd be happy working with black stuff.
* the surface cosmetic may have been the reason I got a good deal on a good quantity.

APAC 564 paste advesive
The waterborne acrylic mastic I found is essentially as odorless as the ensolite. Probably find pastes like it now available at bigbox.
Working and sweating inside the boat without solvents and sweet lethal ordors is a pleasure really. [The adhesive is APAC564 - it has some special attributes. Company makes a family of stickums. Remember talking with a saleman who, after explaining my intended boat use, recommended 564.
After 'troweling' both surfaces, you let it sit for a short time (minutes, depending on temp and humidity) and the piece you are putting on will grab immediately. With varying degrees of dry/wet you can reposition the piece if it is still wet enough. That's one thing that makes this adhesive useful. Another is what they call 'resiliant'. Have used the adhesive as an impromptu filler. When set the exposed adhesive acts like 'resiliant' rubber.
Excellent 'sheer, peel, green & bond strength - anti-microbial, solvent free, 5cycle freeze/thaw stable.' Comes in a 4gal bucket. google the tech data sheet. Recommend it for ensolite. Got it through a flooring contractor.] Acquire some 3" - 4" small V-tooth PLASTIC spreaders. RedDevil - Hyde.
Adhesive is a non-immersion product. Imco if you leave no cracks, openings or voids for water to condense or sit in, this stuff works fine! IMCO !

So the vinyl is from McMasterCarr (pg3508). 5' wide, $5 a foot, .027" thick. Maybe not standard drygoods - it's 'sun, water, mildew & tear resistant' and white. You can see the sheet has a grid, and it has a shiny side and matt side. I've put the matt side out, but dirt likes it. And maybe mould too, but being vinyl should clean up by wiping with detergent. Check out exterior vinyls at SeattleFabrics.com/

I also have some nice tan polyethylene (NOT polypropylene) automobile liner material that I was/am going to use. It's the 1/4" thick hairy stuff you used to see on seat and door panels. Even tho water falls out of it, not so sure I'll use much of it to cover the sponge. But it's nicer to lean against, put a bare arm or foot on, much nicer than clammy vinyl (or bare ensolite) where you bunk.

So I'm covering the rubber insulation. Which of course is not absolutely necessary.
It does keep me from splashing the boat and going sailing.

The white acrylic paste is very sticky stuff. But not viscous like rubber cement. It does produce an absolute bond if you slather it on (with a 1/16" toothed plastic spatula) both surfaces - leave them open for a short period. Since it's not contact cement, you do have a small positioning window applying the ensolite against the hull or the floppy vinyl sheet on the ensolite. However you need faith if you paste on wet that the wonderful water resistance of both materials will allow enough water vapor to escape to produce bond. You need to fool around with the materials.
The peel&stick version of ensolite sounds convenient - BUT you get NO repositioning grace. Once it grabs, that's it! Stckum on one surface only.

The ensolite I'm using is firm enough to actually block sand rounded corners, etc on the edges to get a really tight void free fit against the hull.
As for longevity, the foam is found in gyms and outside at pools. It's your traditional camping and yoga mat. Lit avoids mentioning UV or weatherability. But I looped a narrow strip of ensolite around an outdoor sawhorse that lasted at least two years exposed. Disappeared during a clean-up frenzy. It lightened up in color, stay bendy and didn't crack or shrink like you might expect.

Have fun