Wet foam

[zopperman]

How much of a problem is wet foam?
IS it really weighing down my boat that much?
I've been removing it and it doesn't seem that heavy to me. However, i'm guessing that it can hold water and help rot the floor from underneath?
How important is it to put new foam in the boat? Doesn't foam just add weight whether it is wet or dry?
I feel as though it would be better to have just air pockets instead of foam... someone please educate me!

 

[zopperman]

Re: Wet foam

PS I know the foam provides some structural support, but I was considering either adding more wood underneath the deck to compensate or using home depot spray foam. I definitely cannot afford pourable foam.

 

[rickryder]

Re: Wet foam

It's called flotation foam for a good reason....besides it helps deadens sound and add some structural strength.....it's to keep your boat from sinking to the bottom...The foam adds buoyancy to help it stay afloat while waiting for rescue.


Look in my resto thread.... I used the blue inso foam board.... it will keep you floating

 

[zopperman]

Re: Wet foam

Hopefully it won't come to that.

I've read that pool noodles or plastic bottles are just as effective for floation... thoughts?
and any ideas on my spray foam idea?

 

[rickryder]

Re: Wet foam

The Great Stuff is great for houses but not boats.... That stuff will absorb water.....

 

[oops!]

Re: Wet foam

hi....welcome to iboats dry dock

foam is a real issue in a builders process.

foam is required by manufacturers of boats under 25 feet.
it is not required if you build or restore the boat your self, so....that decesion is up to you.

the reason for the foam in the laws eyes.....is that if the boat gets swamped with water, it will not sink, but rather lay partially submerged giving any humans somthing to hang on to in the water, increasing there chances of survival.

some hulls, are built with the foam in the design of the boat. this means, due to the excellent anti crush strength of foam. they can use thinner hulls, lessen the weight of the hull, and still have a strong boat. bayliner is an example, as well......the famous boston whaler.
the other plus of the foam is that if the hull is penetrated....the water will seep into the hull rather than gush in and instantly sink the boat.......a penetrated hull can go unnoticed for years till the foam gets waterlogged enough that the operator finally inspects the condition of the boat.

the problem is that if the hull is penetrated, the water cant get out of the foamed chamber, and over time the foam starts to get waterlogged. a waterlogged boat is very heavy, as water weighs 8 lbs per gallon.

wet foam living against a stringer, will eventually start to rot wooden stringers with poor fiberglass lamination.

in your case.....i would dig out only the wet foam......any moisture and its gotta come out....leave the rest.
just leave your self enough room to glass in new stringers and then pour in new foam over the old.
btw....the wet foam is only at the bottom......if its totally dry....all the way to the bottom, leave it.

you have stated that you dont want the foam back in the boat.......thats your choice.....but remember...if the hull gets penetrated...the boat goes straight to davy jones locker. no hope of recovery.....and it can happen very fast.......in under 15 seconds....a swamped boat can dissappear under the waves.
that is not enough time to even recover from the impact or accident before the boat is gone from under you, never mind handing out life jackets and shouting instructions.
for this reason.....the builders are trying to find an alternative, rather than foam...but other means of flotation. even empty 2 liter pop bottles.

there are several alternatives to foam.....pool noodles are just being tested for long term benefits. some of the guys here have had noodles in thier boats for two years now. but the 30 year jury is still out.
in the link in my signature below this..... about one or two pages from the last....is a detailed way to foam your boat with out worry about waterlogging while still getting all the benefits (like anti crush) of the foam. it takes a little more time and money ....but it will work.

good luck with your decision...
the choice is yours and yours alone.....its YOUR BOAT and you can do what ever you want with it !

cheers
oops

 

[zopperman]

Re: Wet foam

Yeah.. it claims to be water resistant but I think I'm going to test some of it in a jar of water and see how much it absorbs and all. I would also probably coat it in epoxy...

 

[zopperman]

Re: Wet foam

Wow! Thanks for the lengthy reply. I don't need the boat to last another 30 years.

ALL the foam is soaked and I probably should have mentioned this, but she's a starcraft fiberglass. STringers are all OK and dry despite the rotted floor and wet foam. I'm less worrid about the boat taking on water and sinking as much as I am just general performance. will foam make it plane better or go faster?

 

[oops!]

Re: Wet foam

it is possible that the foam will add stiffness to the hull .....in the case of hull speed......a flexing hull is a hooking hull. ( as the water pushes against the plaining surface of the hull) in smaller boats inder 25 feet...is not so much.....but larger or longer....it will flex a lot, there for slow you down.

will you notice the performance loss....i doubt it......after you dig out the wet foam......you will loose about 300 lbs......so what you pick up....you wont notice in the flex.

now.....here is a test for you.......after the hull is void of foam......walk up and down the hull......push against the hull.....if the glass moves alot its too weak....you can add another layer of 1708 and it will stiffen the hull enough that you need not worry about the anti crush the foam provided.
however.....i think the starcraft boats did not need the extra layer of glass if the foam was removed. due to the thickness of the hull

 

[zopperman]

Re: Wet foam

Hm, yeah, the hull seems very thick. I think what I'm going to do is remove all the wet foam (all of the foam -- it's soaked -- I have NO IDEA how my stringers survived...) then add pool noodles and bottles as a less expensive form of flotation and then try adding some pray foam to keep those steady so they don't rock underneath the deck. Does this sound reasonable? this is also assuming that i find a spray foam that can "pass" the water test that I subject it to.

 

[zopperman]

Re: Wet foam

Does that sound like a plausible option?

 

[oops!]

Re: Wet foam

nope.......the spray foam is carp.

if you are going to add any foam....use the proper two part pour in foam.

it is cheaper than the canned stuff....expencive any way you do it......but. the pour in foam gives you a bigger bang for your buck

 

[zopperman]

Re: Wet foam

yeah, I guess that's the plan then.. Fill the gaps between the noodles with foam! Should I Epoxy the noodles or something to make them more water tight?

 

[Woodonglass]

Re: Wet foam

Nope, no adhesive required. Buy enuf of em to pack em in tight so when you lay the deck it will kinda squeeze em down in place.

 

[littlehero]

Re: Wet foam

As far as cost, I just poured in my foam and I used US Composites 16lb kit of 2lb foam. It was considerably cheaper than anywhere else I have found. I know its uncool to advertise someone else on iboats but it was the cost effective option that worked for me: http://www.uscomposites.com/foam.html

 

[MTboatguy]

Re: Wet foam

DO NOT use the spray in foam from home depot, I am in the process of replacing my floor and that is what the guy that owned it before me did, talk about a real mess and it is very heavy from being submerged in water. As others have stated if you can't or don't want to use the proper foam, use an alternative like the pool noodles or blue board/pink board foam.

 

[ezmobee]

Re: Wet foam

Check out this project http://picasaweb.google.com/pacerdude/EntireDeckReplacement89Celebrity224se#5305852018165355202 used the pink foam sheets. Worked great.

 

[zopperman]

Re: Wet foam

The foam board seems to be great... Spray foam is OUT! I just finished pulling my first trash bag full of foam and decided to weigh it since i was amazed at how heavy it was -- 56 lbs and that was just one section between stringers. I think I'm going to try either noodles or sheet foam like, that.