will foam ever dry out ? budget floor ideas

leserz

Petty Officer 3rd Class
Joined
Feb 2, 2003
Messages
81
i have a small 14 ft tri hull floor is 56" wide. the floor is nothing but mush. the ply wood floor is wet saw dust now. the foam under is soaking wet. will it ever dry out? its a kind of dense foam from a 1975 boat. the stringers that were there are long gone from rot. looks like they were around 1 1/2"x 4" tall at the transom tapering down to 1" in front. also they were not glassed in looks like they slapped some resin on the bottom of the stringer sprayed foam in it to hold them up then laid 1/4 to 3/8" ply down then a 2-4 oz glass cloth over the wood. . i'm not going to spend 400.00 to fix a $100.00 boat. the boat is a 1975 model i'm a 1946 model .LOL can i just cut some pine 2x4 for the stringers and put down exterior ply floor over the foam if it ever will dry out . or could i just build a back porch type deck over the stringers. that way theres air circulation all the time. with or with out the foam. theres foam under the gunnel's. a boat maker a long time ago said to figure out how much floatation you need is to remember a fiber glass boat will float 1/3 its own weight. if i can get 3-4 years out of it thats what i'm looking to hope for. sorry if i'm jumping around in my discription.
 

tashasdaddy

Honorary Moderator Emeritus
Joined
Nov 11, 2005
Messages
51,019
Re: will foam ever dry out ? budget floor ideas

the foam will take years to dry out, if you leave the boat as it is, with the bow up and covered so it won't get wet. but it has now been premeated, it will readily absorb, new water. get the crud out. whether you replace it is up to you.
 
Joined
Mar 27, 2008
Messages
6
Re: will foam ever dry out ? budget floor ideas

Best to get all old wet foam out.Its just adding alot of extra weight.
I use a small hand grinder with the cupped type steel brush eats it up but wear protection and have a good shopvac handy.
 

tmcalavy

Rear Admiral
Joined
Aug 29, 2001
Messages
4,005
Re: will foam ever dry out ? budget floor ideas

Yeah, need to dig that old wet foam out then decide if you want to replace it. Most folks use exterior grade ply coated/encapsulated with resin to waterproof it. Same with stringers. Glass them in, drop in the glassed deck, tie the deck down and off you go...unless you decide to get fancy with carpet, etc.
 

markedman

Cadet
Joined
Mar 10, 2008
Messages
24
Re: will foam ever dry out ? budget floor ideas

I'm telling the same sad story in another thread.

I pulled my boat in a warm garage took off the deck put a box fan under the bow and left it a week...

foam dried 1/4" deep

I dug out more foam, got taken off the project for another week... came back dug out more... still soppy wet and I had 3 cracks in the bottom of the hull for the water to drain.

My vast experience (in the middle of my first attempt lol) says the boat won't dry in anything called "reasonable time":(

Sorry

PS I am sorta kinda maybe well just a little bit enjoying, no... enjoying is too strong a word well the situation is not entirely disagreeable in reguard to fixin my boat.

Hope I encouraged you:D:D
 

tashasdaddy

Honorary Moderator Emeritus
Joined
Nov 11, 2005
Messages
51,019
Re: will foam ever dry out ? budget floor ideas

enjoyable, man it's addicting. i can't remember all i have done.
 

leserz

Petty Officer 3rd Class
Joined
Feb 2, 2003
Messages
81
Re: will foam ever dry out ? budget floor ideas

ok thanks i will remove the foam. i think i can use a putty scraper the hull has a nice woven cloth lay up . no chopper was used .
so what do you think on using a porch deck as a floor use 1/4" space between each board.?
 

oops!

Supreme Mariner
Joined
Oct 18, 2007
Messages
12,932
Re: will foam ever dry out ? budget floor ideas

ok thanks i will remove the foam. i think i can use a putty scraper the hull has a nice woven cloth lay up . no chopper was used .
so what do you think on using a porch deck as a floor use 1/4" space between each board.?

your boat....build it how you want.


my friend uses the wide end of a pic axe to remove foam in a minit or two
 

tmcalavy

Rear Admiral
Joined
Aug 29, 2001
Messages
4,005
Re: will foam ever dry out ? budget floor ideas

Like the man said, it's your boat so make it the way you want. Lots of boats have slatted wooden floors, most are made in removeable panels to make maintenance easier. Check out some boats in your area and online and see what appeals to you, then put your thinking cap on and get er done.
 

LARSON69

Seaman Apprentice
Joined
Mar 31, 2008
Messages
31
Re: will foam ever dry out ? budget floor ideas

I'm working the same issue. I took a 1 1/8 spade drill bit and drilled holes in the foam about 2 inches apart(be carefull not to drill to far of course) so that air can get into it. I left it in the warm sunshine for 1 day so far and it seems to be drying out. My boat is a 1969 18' Trihull. I want to keep as much original as possible so I came up with this idea. If the foam dries I plan on using Great Stuff Foam from Lowes or wherever to fill in the holes. I don't see why it wouldn't dry if exposed to warm temps/sunshine/air. Good Luck
 

oops!

Supreme Mariner
Joined
Oct 18, 2007
Messages
12,932
Re: will foam ever dry out ? budget floor ideas

I'm working the same issue. I took a 1 1/8 spade drill bit and drilled holes in the foam about 2 inches apart(be carefull not to drill to far of course) so that air can get into it. I left it in the warm sunshine for 1 day so far and it seems to be drying out. My boat is a 1969 18' Trihull. I want to keep as much original as possible so I came up with this idea. If the foam dries I plan on using Great Stuff Foam from Lowes or wherever to fill in the holes. I don't see why it wouldn't dry if exposed to warm temps/sunshine/air. Good Luck


hi larson welcome to i boats.....read this

the foam will take years to dry out, if you leave the boat as it is, with the bow up and covered so it won't get wet. but it has now been premeated, it will readily absorb, new water. get the crud out. whether you replace it is up to you.

tashasdaddy is one ot the top restorers on the site ....and hes right

...i dont wanna say your wasting yout time....but your waisting your time ;)

take it all out.....as said.....replacement is up to you
 

leserz

Petty Officer 3rd Class
Joined
Feb 2, 2003
Messages
81
Re: will foam ever dry out ? budget floor ideas

i removed the foam today i used a putty knife came off the floor very easy and clean. took about one hour. the foam under the front casting is bone dry all the way through . so i'm leaving that alone. i bet there was at least 50 lbs of water in the foam alone. not counting the wood thats all pulp thats gone with the foam. i now can lift the front of the trailer with one hand easy now with out a motor on the boat. before i removed the floor i needed both hands to lift the front and needed some mussel. now i need to figure out what i'm going to use for stringers.
 

Mark42

Fleet Admiral
Joined
Oct 8, 2003
Messages
9,334
Re: will foam ever dry out ? budget floor ideas

The good news is that after you take out the old foam, the new foams available are much better. Tests show they don't absorb water readily even when anchored in deep water for long periods of time.

BTW, the USCG does not recomend putting foam under the floor anymore. I read where they suggest filling areas above the floor so that if the boat gets swamped, it will continue to float upright. Boats with foamed floors have a tendency to roll over when swamped. So the question is if your boat gets swamped do you want to be sitting in it, or hanging on the hull as it floats upside down?
 

Coors

Captain
Joined
Dec 8, 2006
Messages
3,367
Re: will foam ever dry out ? budget floor ideas

The good news is that after you take out the old foam, the new foams available are much better. Tests show they don't absorb water readily even when anchored in deep water for long periods of time.

BTW, the USCG does not recomend putting foam under the floor anymore. I read where they suggest filling areas above the floor so that if the boat gets swamped, it will continue to float upright. Boats with foamed floors have a tendency to roll over when swamped. So the question is if your boat gets swamped do you want to be sitting in it, or hanging on the hull as it floats upside down?

Fantastic- the government finally had a good idea.
 

Coors

Captain
Joined
Dec 8, 2006
Messages
3,367
Re: will foam ever dry out ? budget floor ideas

If you don't seal the deck. rot will continue
 

leserz

Petty Officer 3rd Class
Joined
Feb 2, 2003
Messages
81
Re: will foam ever dry out ? budget floor ideas

i still have foam under the gunnel's under the front deck i will look for something to stick in the rear. the boat might be used with a electric trolling motor only. so if i need to ad some flotation i will not need much.. i'm also taking pic's as i go along with the work.
 

reelfishin

Captain
Joined
Mar 19, 2007
Messages
3,050
Re: will foam ever dry out ? budget floor ideas

On the idea of drying out old foam, I have a 10' unknown hull with a foam filled lower hull, it was soaking wet when I found it last year about this time. Not having time to deal with it, I stood it up against the back wall of my shop. It's been there for a year now, inside a heated building with no exposure to rain. The boat is a full foam hull, basically an upper and lower cap pumped full of foam with no stringers. The foam is accessible through a storage box and through two drain plugs at the rear on each side. It drained water for the first two months, then subsided but didn't seem to lose any weight. I laid the boat down last week on it's top on the clean floor and water ran out of all the upper openings, the drain holes are clear but the foam retained the water. It's as soaked now as it was then. Nothing short of separating the upper and lower halves and digging out all the foam will fix the problem. In this case it means the boat will get scrapped, its just not worth the work to save a boat like this to me, the foam is part of the structure and it will take far more work than I deem worth my while to separate the two halves safely. The cost of the new foam alone would exceed the value of the boat in this case.

You did the right thing in tossing the foam, I would look at adding foam in bulk pieces rather than the pour in type, those float noodles are made of the type of foam I like best. I found a load of that stuff at a local packaging company, it can be bought in sheets much like cardboard. I will be using it on most all of my boats from now on. It stands up to just about anything, even gasoline. I have a piece of it which I used to pad corner of the my work bench about 20 years ago, it's been exposed to gas, carb cleaner and all sorts of solvents as well as sunlight and it's as good as the day I nailed it to the bench corner.
That stuff will float forever and I've never seen it soak up water. Some pipe insulation is made of the same type of foam as well.

Many Starcraft boats that I've had have had it below the deck as well.
 

Coors

Captain
Joined
Dec 8, 2006
Messages
3,367
Re: will foam ever dry out ? budget floor ideas

Does that foam have a brand name? Sounds good.
 

keithinil

Recruit
Joined
Oct 1, 2007
Messages
5
Re: will foam ever dry out ? budget floor ideas

Just starting the same type project and I will try to post pics in a new thread. My question to this post is has anyone ever tried using the resin type floor decking like you see at Lowes for outdoor decks both for the stringers and for the decking. Also this may sound stupid but has abyone ever tried using empty 2 liter soda bottles with the cap screwd back on under the decking between the stringers for a cheep flotation?
 

Lou C

Supreme Mariner
Joined
Nov 10, 2002
Messages
13,099
Re: will foam ever dry out ? budget floor ideas

If you're going to put your life in this thing, even if it's a $100 boat, I'd do it right. Pulling out the foam is not fun but do-able. I ripped out the wet foam from an area about 7.5' wide and 6' long, from the helm seats to the motor compartment. The foam in front of and behind that was not wet at all, all the way down to the bottom. The foam I removed was only wet at the lowest 1/8th inch or so from the hull. The new stuff I put in was the HyBond stuff you can get from Jamestown Distributors. It's a messy job but gives the hull and deck much more stiffness than without.

To rip out the foam I used 2 crow bars, one in each hand and I did it in the summer, hot day. Try to do it on a cool day so you don't get heat exhaustion!
 
Top