pourable or 2in foam board

the long of the short is i need to replace foam in 16ft aluminum hull. what do you think whats pros and cons of either.

thanks tony

Re: pourable or 2in foam board

Pros:

2" foam board is cheaper and is just as buoyant.

2 part foam adheres to your hull and you don't have to worry about your deck fasteners pulling out if the boat starts taking on water.

Cons

Foam board won't adhere to the hull and may rip your decking out if it isn't fastened well enough when your boat starts taking on water.

2 Part foam is more expensive.



You can cut the cost of the 2 part foam by using sheet and 2 part combined.

Mix up the expanding foam and pour a thin layer out (small batch) then embed a pre cut of sheet foam into the expanding. After the expanding foam has cured around the sheet foam pour another batch of expanding on top of it (another small batch). This will lessen the amount of expanding foam needed and will adhere the floatation foam to your hull.

Re: pourable or 2in foam board

The biggest issue in my book (short version), expanding foam doesn't drain. Alternative methods (foam board) is used a lot around the iboats drydock in an effort to provide drainage.

Cheers

Re: pourable or 2in foam board

Did I miss something? When did someone's deck pull out of a sinking boat? My suggestion would be to stay away from the poured in crap.

Re: pourable or 2in foam board

pourable polyurethane foam can stand fuel without melting. Soak blue or pink board in gas and see what happens. Having said that there should not be any gas in your boat anyway. But if you had a spill under the deck it would ruin your foam. There is an aluminum boat company out there using both as suggested by jigngrub, but they don't count the blueboard as part of the coast guard requirement for level flotation.

Re: pourable or 2in foam board

Don't forget pool noodles and Tide jugs, good, bad or indifferent, that's what I've got under mine. I do have a bouncy spot where the one span between crossmembers was 2 feet. I'm going to change out the bottom deck carpet for a piece of vinyl over the winter. I'm just about certain I will cut some 3 inch holes and pour a bit of 2 part foam on each side to try to firm the deck up right there while I have the carpet up.
If you use only noodles or foam board consider the lack of support that you'll have after. My boat came from the factory with 1/2 in decks that were quite solid with the poured foam right up against them, but the 1/2 decks in it now are just a little bouncy without the foam support. The only place it is real noticeable is in the 2 foot gap in the crossmembers.

Although it doesn't bother me my boat is noticeably louder without the foam under the deck also.

Re: pourable or 2in foam board

pour in is easy to use and does add surport. the cost is high but not realy that bad considering the time it saves and the places it can be used that foam board can not like under the seats etc. i can see no problem with using either or both. my personal prefrence is to use all pour foam as its cheaper and easier to have that delivered then it was to pick up the foam board then cut it to size etc

Re: pourable or 2in foam board

Glenn can you give me a suggestion for easy to use affordable foam? I will need a small amount and I was figuring on a couple of those spray cans.

Re: pourable or 2in foam board

http://www.uscomposites.com/foam.html

$22.50 for the 4 lb/2 cubic ft. kit of 2 lb. density.

Re: pourable or 2in foam board

I have one squeak near the stern/starboard side in my Islander. I think it may be rubbing just a little on one of my alum stringers back there.

Since I haven't yet laid the finish paint I thought I may drill a few small holes and run some expanding foam back there to tighten it up.

Ah, just talking out loud here I guess