Insulating the hull questions.

[Tony G]

You gotta figure a thousand minds are better than one half. So who has read or experienced what, thought or been told or has it on 'good authority' as to the prefered technique when it comes to insulating the hull?

Peviously I read insulate everything from the overhead to the cabin sole. Then someone stated that below the waterline insulation would trap condensation making an ideal environment for mold growth. The counter argument suggests that you want 'insulation' from the temperature of the water,be it warm or cold. Then some say, no, it's the heat of the sun we need insulation from. Then somewhere along the way it was postulated that panels of insulation may actually provide cover for insects and cockroaches!

I recall Tim L. using rigid foil backed insulation in the salon on Glissando and, what I thought was genious, carpet runners in her lockers below the waterline. The little gripper spikes held the plastic off of the hull thereby allowing any condensate to trickle to the bottom of the locker and out a weephole. But what if you've made theoretical water tight lockers?

I really don't like the idea of gluing anything to the hull-'don't know why but something from the back of my mind says don't do it. I really only gave consideration to insulating behind the ash ceiling strips. Which, now that I think about it is about as sound as insulating your house but leaving the windows and doors open (reference first sentance of post now).

Who has the goods? What route have others here taken? What works, what doesn't? Once we get this mundane rigamaroe out of the way we can move on to more pressing topics like wine racks!!

[Westgate]

Tony:

There is a good thread on the Plastic Classic site on this topic. Many different techniques/ideas are presented. Perhaps you have already visited but figured it was worth a mention.

Andrew

[ebb]

Have some 1/2" sheet pieces of very light white foam loose in the back of the truck. I knelt on it, put tool boxes on it, stuffed it around things that needed to be imobilized. Tough material. Been there for a year or more - I mean it has some permanent dents - but I won't bet on it. It's amazing stuff. You see it used for packing.
It's called Ethafoam. It was real cheap when I bought it at TAP Plastics. It is bendy and pliable, cuts with knife or scissors. It's CLOSED CELL polyethylene foam. It would be perfect insulation if you could find something to stick to the hull with!
One of its great qualities is that nothing sticks to it!

Another material worth looking into is Tekfoil (and other brands) which is various layers of bubblewrap and foil and sometimes polyethylene. The foil is coated when it's an outer layer. There are seam tapes and double sided tapes to stick it. I'd experiment with carpet tape.
Again no mastics I'm aware of. But I've heard some people are putting it into boats. To keep condensation at bay imco you have to have to glue whatever insulation tight to the hull without holidays. Dunknow?

Years ago I got a deal on some 1/2" Ensolite - it's a tough, light tan colored, closed cell pvc rubber.
Hours of research to find a non-lethal mastic led me to a waterborne gel/paste called APAC 564. It's a 'green' flooring adhesive for all kinds of vinyl flooring products. Have glued some 'panels' onto the hull in one cockpit locker.
The job was a PITA because I did it after I closed it in - like an idiot. But they're stuck and seem ONE with the hull.

There must be some mastic that will glue polyethylene - maybe APAC has it.
You may think that this is the Age of Aquarius BUT it really is the Age Of Glue.
Thing is if you got hot summers or you're going tropics, the fiberglass is going to get really hot. The stickum has to hold through what?... a 150 degree range?

I also found some nice beige 1/4" cut-pile polyethylene auto 'head-liner' material. Not really insulation. Actually the doors & footwell in my truck is covered with similar stuff. (Polypropylene pile is commonly used for auto and boat liners - imco we want material that doesn't hold water. Water FALLS out of my polar-fleece jackets, made from recycled p.ethylene 7-Up bottles. The auto liner is the same stuff.
(Head-liner in the Dodge is a thin fabric not glued very well to friable foam.)
'Carpet liner' has an amalgamated backing allows it to be cemented onto boat surfaces. Intend to glue it onto the Ensolite in storage areas. In other lockers, imagine cutting hull carpets to fit, but hanging them in with velcro hook & loop, so they can be removed and washed. They'll have insulating and cushioning value in difficult access areas.

Consensus has it, we should insulate the hull above the waterline where rapid changes in temp and humidity causes condensation. So I'll be attempting this. Another good reason is that, as with any insulation, we're warmer in the winter and cooler in the summer. Thinking Hawaii!


May have got the cement thing covered with the acrylic pudding APAC564.
But what do I know about the outgassing of super-heated pvc foam. Pvc does NOT have a good rep. MSDS sheets exist to reveal info that's hidden by 'trade secret' clauses. They've got carcinogentic plastisizers and other ingredients that makes PVC NON-recyclable. Plastic bad boy that has contaminated the oceans and toxified landfills everywhere on the planet.
All clear plastic films are also implicated in toxic horror stories.
So lining the interior of the boat with this stuff is something to be real about.

[Tim D.]

Ebb, I have used a waterproof contact cement like "Barge" for years on closed cell ensolite material to outfit kayaks and canoes. It seems to work fine, I am assuming that either this is not what you are looking for or you find its flammability unacceptable.

[CapnK]

Tony et al -

I have found thru experimentation that Gorilla Glue (and likely its similarly-chemical cousins) can be made into a sort of an 'expanding glue'. You just have to mix it with a lot of water (and fast, and apply it fast - pot life is like maybe 10 minutes).

I will be bonding sheet foam (EPS - pink or blue) to the hull using this. Besides a very strong bond, I think the 'foaming' property will cut down on the "holidays" Ebb mentions. Condensation forms from atmospheric water (humidity), so if you can seal off a small area, you shouldn't have that as a problem. I'll be adding a layer of luan/doorskin ply to the outside (the cabin-side) of the foam, and a layer of 10oz glass over that to protect it and make a durable, easily-cleaned surface. Because the EPS foam will be behind wood, I will be able to use cheaper polyester resin instead of epoxy when glassing over it (People may poo-poo polyester it seems, but the stuff has held the boat together fine for the last 40 years, so I have no problems using it where I can!).

I'd like to sneak in a radiant barrier right up against the hull if I can. A layer of mylar 'space blanket' material would work great, or maybe aluminum foil. Have to play with that a bit yet, make up some test pieces, see if the GG can bond to either of those materials, or if I'll need to perforate it...

I'll be putting insulation (AKA 'flotation' ) against every bit of hull I can, above and below waterline. Condensation forms all over, everywhere - I have seen it often in the past 4 years of living aboard. It is a bit more prevalent below the waterline, when conditions are right - but that is not always. I also want to treat the overhead in the v-berth, somehow...

I like the GG because I think once it is cured, it will not 'outgas' much, if at all, and seems to be a really stable substance. The other material I considered was something like 4200/5200, but the GG can do the same job for much less money and mess. I want whatever it is to be pretty much permanent - it would suck to have your hull insulation/liner delaminate after a few years, and my experiments with other glues like contact cement, Goops, acrylics, and such showed me that you need to make sure it is a really good bond, when going up against the hull. Most of these failed to some degree. GG becomes an inert solid after it has set up, whereas the rubbery adhesives are always slowly degrading (outgassing) to some degree - losing some of the very stuff that makes them what they are. How long until that has an adverse effect on the job they are doing? Your guess is as good as mine. So I am opting for a glue which does not have that propensity.

I like the idea of solidly encapsulating a solid foam (as opposed to gluing in a pliable foam) because it seems that would hold the materials in stasis better, for longer. If balsa can stay as dry as it does in the deck for 40 years (assuming no water penetration), so that it looks like it was installed yesterday when brought into the light, it just seems to me that encapsulation is the way to go.

[ebb]

Kurt, we have talked about your pink foam idea befor, so excuse me please if I repeat stuff. Pink and blue foams are relatively stiff sheet POLYSTYRENE FOAM insulation usually found at the big box depots.
Small panels could be heated and softened and pushed into the compound curves of an A/C hull. The compound curves are essentially minor in small sections. Gorilla polyurethane glue though is fairly expensive. But probably a good choice considering hull heat and cold cycling.
I think the pink foam is gluable with anumber of mastics - I wonder if tube 'threshold cement' could be used? Or perhaps tube glazing caulks/sealants (not silicone) that are formulated more toward heat extremes than construction goops.
[later EDIT: one structural polyether tube goop, I can recommend, is Chemlink M-1, considered green, non-toxic, bonds almost everything.
But haven't used it for the purpose here myself. There may be a problem getting it to set if no air moisture can get to the glue under closed cell stuff. It may not matter becauwse it begins setting immediately. So after tooling it on both surfaces with a toothed plaastic spreader, the open time may have been enough of a catalyst to promote it becoming rubber. More elastic formula Chemlink Novolac might be better for this app.]

I agree that polystyrene should be encapsulated.
As you say to protect the boat's interior from the foam's outgassing when the hull is heated by the sun or the ship's stove.
The encapsulation might also be augmented with paints. A good one imco would be a waterborne rubber urethane. As in deck paint without the antiskid.
Or an acrylic latex exterior house paint.
The encapsulation is suspect too, even plywood has formaldhyde in the glue.
SO encapsulate with glass or ceramic!!

Polyethylene foams don't have the same outgassing problems that the Bisphenol A toxin group has.
Note that when this foam burns it doesn't produce lethal smoke - which can't be said for other foams.
Who knows for sure? To be safe ALL foam insulation in the enclosed interior of a boat should be encapsulated.
Ensolite is used for a host of consumer products, everything from kneepads to yoga mats, and Airex is the same stuff in expensive closed cell mattress form. Bad chemicals. Goodlord maybe warmed up gelcoat and epoxy paint will compromise my tired immune system.

Tim,
I'm old enough to believe that that most of my body's complaints is due to decades of direct exposure to chemicals/solvents I've used. I think most of my toxic episodes are cumulative. Once thought the liver and kidneys where born-again and repairable.
NOW I go nuts trying to find less lethal materials to use on the boat,
especially inside.
Can't work with a canister mask on - besides having a beard which screws up a mask's breathing seal.
That non-toxic floor adhesive is not bad stuff - altho finding it was a problem.
Waterborne glue takes longer to set up than solvent glues - especially when you're gluing on closed cell material! Might ask if it ever sets up in some places? You have to be able to hold it in place by putting props or pressure on the panels.

California has led the way in safer products. You can legislate the great corporate planet polluters into making more friendly products.
But never turn your back on those jerks. Remember WCField's first law of consumerism:
"Never give a sucker an even break - or smarten up a chump."

[CapnK]

Right-o, Mr Ebb - sorry for the shorthand, should've explained: "EPS" stands for "Extruded PolyStyrene". Can be used with epoxy resin, but not polyester, generally; polyester resin has as a component styrene, which will dissolve EPS foam (you can use polyester resin with EPS foam and get minimal melting damage to the foam, if you kick the resin hard and fast, but... it's dicey. Better not to.).

I am simply going to kerf the foam sheets to get them to conform to the hull curves. Most of the sections are short, so there is not a lot of conforming to be done. Can always fill in any big kerf holes with epoxy and microballoons also.

I tried a buncha glues out. Lots of them will dissolve the foam. Styrene? Dunno, but something in there doesn't like it. On the advice of a 'long time flooring professional' guy who was working at one of the BigBox hardware stores, I tried some really tough floor glue prior to GG. Turns out that on these materials it only bonds here and there... Strong, remains adhesive, but just won't be consistent with grabbing the foam or the ply. Have two 4'x8' sheets of that made up already... Going to try to stick GG in there and see if it will hold well enough that I don't have to waste the material. If so, will use that for less structural stuff.

A guy on another sailing board I read swears by Glidden Porch and Floor for a cheap hard boat paint. Seems like it is a 1-part epoxy. At $25/gal, it's darned affordable, so I am going to get a small bit and check it out. Might be great for a finish on the interior. I have read of others who use garage floor paint also. Likely, any 1-part epoxy paint will do well for this application.

[ebb]

Hey Kurt,
I'm just assuming that ANY waterborne (aka NON-SOLVENT) mastic/glue will not eat up polystyrene. Adhesives formulated with solvents are there to make the adhesive set up faster. Commercial outfits want fast materials - to hell with the worker's health. Waterborne flooring adhesive paste which you put on with a toothed trowel would give abundant coverage. I've already successfully stuck Ensolite with it. Putting foam everywhere is a lot of square footage!

Beware of one part epoxy coatings. Very often the only epoxy in them is 'epoxy solids' - whatever that is.
Somewhere else on this Board I was just saying that I am about to use a TWO-PART WATERBORNE EPOXY ENAMEL. These words until recently have never been used in the same phrase together - but coating chemistry is radically changing these days, probably because of new stringent LowVoc and HazMat regulations.

The coating I'm trying out for the first time has many attributes of solvent and 100% solids epoxy. High adhesion, chemical and acid resistance, resists strong cleaners, interior/exterior aps. It also has low odor, will cover just about anything (has more flex than usual epoxy coatings), water clean-up, glossy, and won't lift conventional coatings (no voc solvents).
Has a 6 to 8 hour pot life, sets dry to touch in 30 mins.
Bummer, the stuff has to have a surface temp of 60degrees to apply.
I see it as a finish coat, or if I wish it can scuffed and topcoated with nearly anything else.
Comes in colors. I choose white for the interior of lockers.
It's an institutional coating. I had to pay near $100 for a gallon kit. Better be GOOD! Haven't had 60degrees this year yet.


KURT,
You got me thinking about encapsulating these foams.
You are absolutely correct that if the boat is to be 100% habitable NO foam should be exposed in the interior.

I think that a flexible waterborn polyurethane rubber coating may make a great BARRIER.
I have a gallon of white UTRA-TUFF I'll try. It is a one part coating - the kind you'd paint onto your boat deck with rubber granules mixed in it.
Mine's special order plain. It ought to stick perfectly on the Ensolite and be flexible enough to never crack.
It's a quranteed to never leak and to always have 100% elongation. So my assumption is that it would make the perfect foam barrier, eh what?

This is a highly touted abrasive resistant DECK coating. Should also protect the foam against abrasion, easy to clean, easy to repaint if necessary. It's an all-weather coating and it ain't no fru-fru 60degree stuff - it goes on as low as 40degrees!
http://www.ultratuff.net/utmindex.htm

[Hull376]

Hey gang,

I haven't posted in awhile but I'm still lurking out there. I'm tired of condensation and resulting mold inside Charisma during spring and fall, with rapid temp changes turning humid air into liquid h2o. Would be a fine discovery if liquid water is found on Mars by the Curiosity Mini car, but I don't want it in my boat anymore. And then there is Texas heat which taxes any air conditioner in an uninsulated boat. I've been reading all the cruisers boards on insulation, and as you'd expect, sailors have lots of opinions! Some go the spray in foam approach (messy) others the pink, yellow aluminum faced, or blue sheet foam board big box store solutions. Others like mineral wool, cork, carpet, or just bigger heaters, coolers, or moving boats North or South. Most say don't use anything that can ever absorb water, or ever come detached from the hull. Unless you want to grow an Andromeda strain of bacteria between the hull and the insulation. One product that gets good reviews except for the cost is an engineered foam rubber called Armacell which was developed for insulating high and low temp process piping and ductwork. Operating temps between minus North Pole and halfway to Hell hot. Comes in tubes for pipes and flat sheets 36"x48" in 1/2", 3/4", 1", and 1 1/2" thick. Has super low water absorption, is a water (condensation) barrier, impregnated with mold inhibitor, yet safe for use in school A/C systems with no harmful out gassing. Sheets can be purchased with adhesive applied or you can use formulated adhesive for the product. Adhesive supposed to withstand hellish temps. Smooth outward facing surface can be rolled with latex- their product latex supposedly will stretch withou cracking. A possible negative is that it is a much heavier product than lightweight pu foam. Probably no biggie unless your boat is already loaded down with junk. Maybe go thinner thickness to shed some pounds. There are examples on the web of new construction boats using this stuff instead of spray on foam. Anyone have knowledge or experience with Armacell? One inch has R value of 4.2 vs about 5 with foam board. Ebb, I value your opinions so if you Google Armacell or go to http://www.armacell.us/ insulation products, AP Armaflex sheets (was developed by Armstrong years ago) I'd like to hear what you have to say.

Here is a link to a new construction project and I've seen a few fiberglass hull retrofits on the web http://www.armacell.us/www/armacell/ACwwwAttach.nsf/ansFiles/US_M&O%20_Hull_Insulation_Jobstory.pdf/$FILE/US_M&O%20_Hull_Insulation_Jobstory.pdf.

Ps I just discovered that ensolite is made by Armacell, primarily for the automotive market acoustic attenuation.

[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

[Hull376]

Thanks, ebb. You can still get Ensolite in the tan as far as I can tell from Armacell's website. As luck would have it, we have a local distributor for most of their product line here in Houston, so I plan to to show up and have them show me what they've got. I'm going to grill them about benefits of Ensolite versus some of the other elastomeric foams, such as Armaflex. I tend to agree that light color would be better than black, unless you already have your head around either painting the surface or applying a vinyl fabric. BTW, let us know how the vinyl covering holds up or if you'd do something else if you could rewind tne tape! I've decided that if I do this insulation job, I want to do it right the first time, even if it costs a bit more. I'm trying to get rid of mold and condensation on the hull, and so many of the other solutions may work for awhile, but then fail after a few years and make a real mess. I like your comment about adhesives being tne current "it" product. Staying stuck to the hull is probably the biggest failure risk with these elastomeric foam products. I have visions of a one inch thick sheet detaching from above the V berth, while it may be just fine on more vertical surfaces. Maybe 1/2" on the underside of horizontal surfaces. Something I haven't seen any posts on is injecting pu foam between the coach roof and the inside liner. Doesn't mean it hasn't been discussed already, I just never saw them. Guess I could do a search!

[ebb]

Kent,
Injecting 2-part urethane foam between cabin and liner would be a problem because the pressure created by uncontrolled foam expansion will make your liner bulge like a pregnant dog. Don't believe the process chemicals have changed: reaction gasses are toxic, and because the cells are not truly closed cell the gases can continue to leach out... for (not knowing the stats...) for your forseeable future.
There are single part aerosol construction foams that advertise CONTROLLED EXPANSION - that might actually work. HOWEVER, you cannot prep the inside surfaces of the liner or cabin. Imco when they were made the last coat of polyester had wax added to get it to set hard. Foam that is not sticking in non-accessible places will hold moisture, get smelly & go bad. Don't inject urethane into your boat ! ! !
I believe just about any foam urethane is toxic, it never becomes inert.

Empty air space is a pretty good insulator.
Wonder how much condensation you notice on the cabin liner overhead when your boat is dew-pointing vapor ladened air and the windows are dripping. The top of the coach roof is balsa composite. Where the balsa stops must be before it makes the difficult transition at the corner curve to become plain fiberglass sides. The liner creates a hollow space which may also keep condensation from forming on the cabin sides in the cabin - but condesation may form inside in the damp space between the liner and the coach sides.

Impossible to seal cabin side windows (dead lights).
The strange original Pearson squeeze frame mounting system and floating lenses of the large windows use the bendy unfilled space between the LINER and the PLAIN 1/4" thick sides to make the ineffectual seal of the window frames possible at all. And as everybody knows, the windows are leak prone because of this poor design. It will be impossible to fill the vertical sides of the cabin with 2-part polyurethane foam, you'd have to create difficult jigs to keep the sides from blowing out the liner inside. There is no 'FLAT' to the existing liner. Even outside will billow out in places imco. In use polyurethane foam will disintegrate if it moves at all. There will also be voids & adhesion issues.
Actual partial filling in between liner and cabin sides with epoxy for alternate window systems has threads in this forum.
__________________________________________________ __________________________________________________ _____________

The PVC/foam rubber product is a good candidate for that white paste. Very gluable. There are bigbox products available that will do better than regular contact cement. Better then water based contact cement alternative. What's likable about paste* is that you control thickness with the toothing of the applicator, means you can have less voids between the surfaces (that you will get using thin film high solvent contact cenent).
Have used the acrylic paste to fill seams around the foam cakes - making seamless embedded insulation. You don't have to do that, but no water will seep in and algeanate, no dirt, no little creature hotels. The thicker paste 'filler' eventually dries into a firm flexible rubber, and seems to be completely bonded with foam and various surrounding materials.

Haven't done it myself (we grinded down to green polyester) but if you dewax, clean, abrade and smooth the old painted surface, I'm sure the acrylic paste will stick - better than the old paint you are covering, most of which is bloody bonded to the hull.

Imco you can paint ensolite with flexible rubber urethane deck paint (without the anti-skid in it.) after it's installed.**
Haven't done it specifically. Prefer the smoother shielding surface of vinyl fabric. Which also gets totally bonded to the foam.

I have moral and chemical problems with PEEVEECEE. A UNIVERSALLY BAD PLASTIC. Think it is an unethical irresponsible plastic that in various forms is killing all creatures great and small on the planet. The ensolite I have is so old that its real danger may be its old age. My problem too. The vinyl I just got is low odor, maybe it passed its gasses into the MMC warehouse environment while waiting for my order.
Can't think of any any insulation products that are inert. Maybe balsa, the great insulator - but it rots. There are no CLOSED CELLS in nature...
__________________________________________________ __________________________________________________ ________
*Bostik makes a pleasant smelling, non-toxic, water based acrylic, smooth white paste for cork and carpet tile called InstantPro. The TDS makes it sound similar to the stuff i'm using. Remember I'm also using the 564 as an 'experimental' fillit - with a finger and extra paste radiusing the bottom of an ensolite panel where it butts the settee - to create a mopable waterdam of sorts.**
Open time (very important) discussed in the data sounds like my stuff. "Inside only" - may refer to constant water wet-softening the set glue. Might not use it in the cockpit! I'd worry about inside boat use if the closed cell foam allowed water in! Tend to trust Bostik products. (so far)
__________________________________________________ __________________________________________________ _________
**Have painted white water-based urethane rubber UltraTuff nonskid deckpaint (without granules) into lockers befor they become inaccessable to further painting.. Assume the stuff bonds to any exposed acrylic paste where ensolite was installed - sealing plywood and seams from standing moisture. Also rubber surface might add some traction for objects in the locker that hard stuff can't. Exposed to view, it's a lousey look, imco.

[Hull376]

Ebb,

I very much appreciate your input on this. You know, now that I think about it, it takes a lot longer for any mold to appear on the liner, as you state. So the air, balsa, or whatever the Portuguese builders did with 376 does provide some insulation to reduce instances of reaching the dew point compared with the sides of the hull. I won't fool with it! You've given me ideas on attachment and surface coverings. Most importantly, you've confirmed for me that I'm not crazy to be thinking about using elastomeric foam sheets, PVC or other compound ( my visit to Armacell distributor may help me there) versus other alternatives.

[ebb]

Kent,
There are other fun foam sheet plastics, one of which is Ethafoam.
It is a translucent closedcell bendy polyethylene. BUT we can't glue this more friendly foam to the hull.
Possibly there's a glue by now that we haven't heard about yet. It's way cheaper than ensolite. Used as packing material for shipping.
Requirement may be that the surface of the sheet be pretreated with a propane torch to change its 'surface energy'
and then stuck on with a nice acrylic 'yogurt' paste. Haven't tried this myself !

Armacell also produces wax plastic (polyethylene p.olefin) insulations. They may have a waterborne mastic that sticks it.
NO aromatic solvents, OK? !

Ask the Armacell tech about gluing in the foam insulation he recommends
if it's not an ensolite.
The CLOSED CELL insulation must be firmly attached to the hull. Bonded.
Once it is embedded and bonded, no condensation will form and a good waterborne paste won't be a problem. If it's not continually immersed.
Ensolite in most ways is ideal because it conforms to mild concave surfaces. When gluing in, pushing it against the hull will keep it there.
This means the sheet won't tend to pull back into its flat sheet form (OR create a bulge) when gluing to the hull.... like other less docile foam materials. It's what makes ensolite the only closedcell foam that is also comfortable for expensive flotation cushions and bunk pads.

Also want the glue to bond to the rubber. It's possible that even regular contact cement can be pulled off the foam. Observed this once, it's not something I would swear to.
White carpet layer's paste is something to look into to. Acrylic glues are a minor miracle of sorts. See post #10, APAC 564.
(Defender & others have a liquid waterproof capet adhesive - not described as a paste - tech data sheets seem unavailable at any source. The origin of the carpet adhesive is Redrum Fabrics (makers of Nautilex marine fabric glue). Billed as non-hazardous. It works by
water evaporation in application, like 564, and other waterborne pastes. Forum user complains of material not holding on vertical surface.
Defender - Marine Carpet Adhesive - (Redrum Fabrics)Maple Leaf K-Grip 398, $34.99gal. Waterproof after cure. Is this roller or trowel???

[ I have the acrylic paste and the ethafoam, maybe I should do a test??? ]


You might be persuaded to use tube polyether or polysulfide. (Imco these structural adhesives, including tube urethane are WAY overkill) you'll still have to spred the material with a toothed spatula same as the yummy waterborne stuff - to get total no void coverage - and on both surfaces! Cost hundreds of dollars, and the cruds are viscous and messy to use.
There are no marine tube synthetic rubber caulks that will glue HDPE, polyethylene foam.
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[ Be warned and do your own confirming/testing. So far as I know this method is not supported by public forum. Nor Nigel, Larry, Maine or Don. Nor PracticalSailor or GoodOleBoat.
Personal research and luck (good & bad) led to the method, which seems logical.
And the inside of litlgull seems sucessfully insulated - from sheer to more-or-less waterline - with ensolite and a fine non-toxic cork&carpet paste.
This is.... in my considered opinion. ]

[Hull376]

Ebb,

I got my sheets of Armacell Armaflex after visiting with their distributor in Houston. They said it is the best foam they have for enclosed areas and is used in school HVAC systems. I got 1/2" 36x48" sheets. I also sourced some white vinyl cloth and glued it to one side of each sheet. I tested cutting the sheet with the vinyl using scissors, regular knife, hacksaw blade, box cutter, and electric carving knife. The carving knife was way way superior to the others. Cut like butta! I made patterns with brown paper, and transferred to the sheets. Cutting them with the electric knife was soooooooo easy. Very clean edges, no tearing. I looked at the adhesives, and I decided to take a chance with the 564 enviromentaly friendly adhesive you used. No way do I want to use volatile death chemicals in the cabin. Also, the ability to slightly move the pieces during installation is a selling point versus contact cements. I don't know how I'd get a piece positioned properly with contact stuff.

There is a 564 distributor in Houston so I was able to just pick the stuff up. It cost me $70 for a 4 gallon pail. They don't carry 1 gallon containers. Guess I'll have a lot left over to glue AstroTurf on the decks of my boat and at least 10 others at the marina. The three women at the 564 distributor are into cats (the animals,not the boats!) and tried to get me to adopt one of the kittens that they find from time to time in their warehouse! One kitten sat on the keyboard while my order was being entered. Explains the typos on my invoice! I'll let you know how the installation goes. So far, so good!

I decided to apply the vinyl before cutting and installing, as the prospect of doing the vinyl after insulation seemed beyond my skill or patience level. I'll glue the seams, then stick on a white batten from Lowes using a 3M product for vinyl surfaces. The way I cut the sheets left me with only one seam in each cabin. I don't think that's too much of a distraction!
But I haven't tried to do the pieces for the roof of the V berth yet. Did you do that area and if so, how did you splice the pieces? Looks like several ways to do it.