How Do You Insulate Bare Fiberglass?

[Fortytwo]

Interesting...

Cork Stucco | Jelinek Cork

[o_q]

Originally Posted by The Garbone

The good part of the design is that a few Clorox wipes and its clean and looks good as new. It is amazing the amount of condensation 2 people can cause in that cabin in the winter.

I guess it would be easy to clean, but more important to stay warm. Wouldn't condensation be more a problem with bare fiberglass?

[o_q]

Originally Posted by o_q

I guess it would be easy to clean, but more important to stay warm. Wouldn't condensation be more a problem with bare fiberglass?

Nevermind. I reread your post.

[Katiusha]

Originally Posted by Cotemar

When you insulate the rain (condensation) will stop. Works great under the matresses also

Sorry for a thread drift, but:

Cotemar, so if I install cork under mattress, it will work the same as those air vent systems to prevent mildew forming on the underside of a mattress?

[Mikromidas]

I insulated the whole boat with 13mm Armaflex - Armacell - Armaflex

Then on top of that I used 3mm white expanded vinyl.

Don't use contact cement. Use a MS-Polymer like Tec7 or a cheaper alternative.

It's a lot of work, but worth the effort.

Found an interesting site for fabrics - Outdoor Fabrics Canada - - Sunbrella Distributor

[Cotemar]

Originally Posted by Katiusha

Sorry for a thread drift, but:

Cotemar, so if I install cork under mattress, it will work the same as those air vent systems to prevent mildew forming on the underside of a mattress?

No, No, not cork. I never mentioned cork.

Put Neoprene or the hard pink foam from Home Depot under your bed to stop condensation and mildew.

We used the 1-1/2 hard pink foam under the bed and the condensation stop the same day of installation.

[Captain Bill]

My boat's deck is cored so I already have some built in insulation. In addition the ceiling has 1/2 inch furring strips which are covered with foam backed vinyl which is mounted on thin plywood. These panels screw into the furring strips. We've been on board in the winter and the only condensation we get is on the cabin windows. I'm don't see any real reason you could not just glue it down unless you need to get at something under it now and then. The furring strips allow the panels to be removed so you can access things. If you nedded it I don't see why you couldn't put an extra half inch of insulation between the furring strips. With our cored deck it has never been a problem. On the hull sides our boat has glued down short pile carpet and we've not had any issues with that either.

Good luck

[The Garbone]

Headroom?

Last November we heated ours with a small space heater. It was in the 40s and it was probably only running 40% of the time. Small volume, but condensation was an issue for sure.

[Delfin]

Originally Posted by o_q

I guess it would be easy to clean, but more important to stay warm. Wouldn't condensation be more a problem with bare fiberglass?

Yes, condensation is the issue. That's why the cork is nice. It's only 1/4" thick and it eliminates condensation.

[Roy M]

Having seen the photo, I now retract my advice. Any of the suggestions offered may cause more problems than will get resolved, reducing the market value of the boat. Are you sure you want to do that? If you are having acute condensation problems now, and can clean up the resulting mildew with chlorine beach solution, imagine what will happen when the mildew begins to grow deep inside the cork insulation or behind some foam pads.

The problem may be that your particular boat was built for a different climate. Two people breathing inside a small closed boat, leading to the "rainfall" alluded, tells me that there are bigger problems, specifically poor ventilation to remove the moisture. The problem is that the interior air is moist and warm, the air outside is colder and probably a little drier. I tried many of these solutions when I first moved aboard. The cork developed black patterns what were a real challenge to clean out the bottom of the fissures. Two people breathing inside a closed small fiberglass boat, in a chilly harbor berth is going to lead to "dew" forming on the chilled 'glass surfaces. You have to remove the stale air and replace it with lots of fresh, drier outside air. That will probably mean putting on a sweater or plugging in a heater, WHILE PULLING IN FRESH DRY AIR THROUGH AN OPEN PORT OR TWO. Sorry, but there are no simple solutions for remove condensation from inside closed boats, even of there is no one breathing inside. Warmer air holds moisture, cooler air holds less. Boats are sitting in a big pool of water. If it's warmer inside, it will pick up moisture from the bilge or from the residual dampness of the stuff inside. Open a port, turn on a fan, put on a sweater.

[Delancey]

Originally Posted by o_q

I guess you could spray some insulating foam on it, and call it a day, but I imagine it can be more involved to make it look presentable, or perhaps proper. If I saw a boat like that, I would not want to buy it, and I would think the owner is lazy. But I am ignorant on the matter, so please enlighten me.

What's your objective? Keeping warm, being energy efficient, avoiding condensation? Or maybe all the above?

My wife and I liveaboard a forty footer in the Northeast. To provide for heat we ran a 1500w radiator-type heater in the main cabin and a 400w ceramic panel heater in the head and were pretty cozy most of the time down to temps in the teens.

Our decks are cored fiberglass, we insulated the hull with the aforementioned Reflectix which helped but found a good winter cover had the biggest impact of all of the things we did. I made the cover out of an agricultural tarp material that was clear and allowed sunlight inside, toasty on a sunny day! Cheaper than shrink wrap and reusable. Throwing away a boat unit every season just doesn't make sense to me.

Regardless of these improvements, we found a dehumidifier to be essential for dealing with condensation. You can insulate all you want but you will still have condensation between the insulation and the fiberglass hull unless you glue it down. If you glue it down you are likely creating an environment for mold growth since there are bound to be air pockets in there somewhere.

[muskoka]

o_q

Like Delancy asks: What, where and why? The solutions for a boat in the tropics are completely different for one in the Baltic. You need to be explicit about the details of the boat. And your location.

[hellosailor]

Cote, meaning no aspersion against whatever brand of neoprene you make or sell...

I wouldn't tell anyone to put neoprene on their boat. First off, there's no way to tell if you are buying cheap chemically foamed neoprene, which rises due to chemicals in the "batter" when it is formed. Those shrink, incredibly so, and crumble, if a chemical mix burns them as they age. At least one maker of premium quality (nitrogen-blown instead of chemical) neoprene suggests that only the pricey neoprene-blown stuff will not break down and shrink as it ages.

And it is all expensive compared to other foams. The heavy stuff as used in wetsuits is also damned heavy. Good protection against being thrown around hard objects, but hardly effective to insulate a boat, is that?

[Delfin]

Originally Posted by Katiusha

Sorry for a thread drift, but:

Cotemar, so if I install cork under mattress, it will work the same as those air vent systems to prevent mildew forming on the underside of a mattress?

Yes, Katiusha, it will eliminate condensation, and they will stymie the mildew.

[Strait Shooter]

Originally Posted by Mikromidas

I insulated the whole boat with 13mm Armaflex - Armacell - Armaflex

Then on top of that I used 3mm white expanded vinyl.

Don't use contact cement. Use a MS-Polymer like Tec7 or a cheaper alternative.

It's a lot of work, but worth the effort.

Found an interesting site for fabrics - Outdoor Fabrics Canada - - Sunbrella Distributor

+1 for the Armacell.
Anti fungal, adheres to bare fiberglass well with contact cement eliminating condensation for the most part. I took it a foot below the waterline.

+1 for the reflex foil air bubble stuff too. Great under the fuel tanks, and engine room.

The rigid polypropylene insulation is nasty, ineffective, and I wouldn't have it on a boat....... Well maybe the mattress pad thing is worth trying.

Proper insulation isn't easy, but the payoff is enormous.

Aren't there like a kajillion threads on this already?