Expanding Foam Flotation

Where was the foam, how old, and what type is it? I don't know if all closed cell foam is created equal or not. Do you suggest not using the foam for floatation...I mean some of it is USCG approved for such applications. Or, do you suggest a vapor barrier between the foam and hull?

 

So how did the water get under there in the first place? If they foamed the strakes like they did, there's obviously no way the water could drain. Was the deck not sealed and allowed water to get under the deck, causing it to stay in the foam?

I used the 2 part expanding foam on mine almost exactly the way shown in the pix, but I've also taken great care to make sure the only way to get water/moisture UNDER the deck is a hole in the bottom of the hull. If that happens, I've got bigger issues than the foam taking on water:crazy: The foam is basically filling a watertight space between the hull and bottom of the deck.

I'm not disputing what you're saying about the foam taking on some water, with the application of sufficient pressure over time it makes sense that the closed cells would begin to break down and allow the foam to become more porous. I am saying it sounds to me like the issue isn't with the foam, it's with the application that it was used on, or with a failure (like a hole or leak that let water into what was supposed to be a watertight area) of some other component or system.

The foam is meant to augment the structural stiffness of the boat, provide a margin of safety in case of a hole in what should be a water tight area, or to provide additional bouyancy in case of swamping. It's not meant to compensate for bad design or long-term mitigation of structural defects.

Just my $.02, but I'll take my chances because the benefits of the foam to my application is well worth it's limitations.

I do appreciate the head's up, though, if I hadn't sealed the voids where the foam is you can bet I'd be doing it now after seeing your pix. Thanks!

Branden

 

No, I understand, I didn't mean to criticize what you're saying. I just never thought about it - I've seen the riveted seams around the perimeter of Lowe boats before and never thought about the foam being in constant contact with the bilge water (especially in the position you showed in your diagram).

So there was no foam under the deck and just the foam in the two "boxes" so that the water flowing under the deck was constantly in contact with the foam? If so it makes perfect sense the scenario you describe. Until I saw the pic of the position where the foam was soaked I thought you meant it was between the deck and the floor, that's why I asked about whether the floor was sealed. Again, thanks for the tip, I just didn't understand how the water was getting into the foam.

 

Bilgeless boats are the answer. Maybe one day the aluminum boat manufacturers will figure out and utilize the concept.
Its a saltwater concept that hasn't migrated to the manufacturers that build primarily for freshwater.
Of course aluminum has alot to do with that. You cant do with aluminum what you can with fiberglass or wood. It's a material that is limiting yet a material that is advantagious to the speed of production.
To take aluminum and try to build a boat of the class you see all the time around the big water would slow production and drive the cost of the boats up. Its like taking a Chrysler K car and trying to turn it into a Camaro.
It can be done but its no longer the affordable car for the same volume of people.
You see the same thing in fiberglass boats except its a different set of problems.
Thats why we have umpteen threads about replacing rotted out floors.
A floor can built that will never rot out of wood but the dollar prevails.

Boat compaies are like any other company in the fact that they are in business to turn a profit.
Just because its brand new and just because you financed 25k for it doesn't mean its without flaws.
I've torn into enough boats over the years to know you can hide alot of flaws in the construction of a boat that may or may not ever rear its ugly head depending on the owner, how he uses the boat, and how well he maintains it.

I'm still laughing at 10 guage solid TW wire installed at the factory and foamed in on a bass boat I owned. 10 gauge is alot alot cheaper then 6 gauge welding cable and the trolling motor will work off it. Just not efficiently.

You dont have to mess around boats long to figure out where the money is made.
Fiberglass boats with wood stringers are often chopper gunned. It does absolutely nothing to strengthen or protect the wood. Thats why stringers rot out. Same thing with floors. The wrong material is used to install a material that is capable of working leading to the assumption that wood doesnt belong in boats.

A true 2 part flotation foam belongs in a boat. Like wood, its only as good as the installer. Installed correctly with an understanding of boats you would be hard pressed to ever have a problem with it.
Also I would like to add. In the boats I've torn apart I've found some top notch foam that was dry as bone in a poorly cared for boat and I've had the pleasure of digging out "closed cell flotation foam" that you could wring water out of.
I've even seen the green flower arrangement foam that was sprayed in at the factory as flotation foam.
Truth of the matter is as far as foam goes, you dont have a clue what you are dealing with unless you can see the label on the product and know that what you have came out of that barrel.
There is foam and then there is foam.

If you dont want to spend the money for a good product or you doubt the ability of a good foam to deal with water then by all means build sealed compartments. They are better then foam. Air is lighter then foam.
Foam wont make that boat float any higher in the water then air will.