spray in foam question

What a great site. just reading the post has helped out so much with the planning of my boat project.
I'm going to put new wood decking on my old Alumacraft deep V fishermen. In the bow I'm planning on making compartments for all the little stuff such as tool box, cost guard safety box, extra, under the floor. I want to spray in foam in the open cavities that are not used. What direction should I go? Should I use the can stuff? If so what type should I use? Or should I find a company to spray in the kind used for house insulation? This boat gets used for fishing and duck hunting in open salt water water so I want as much floatation as possible.

Thanks for your input

Damifinow fish

You should be good with the stuff in a can. No need for overkill - just need enough to make sure the boat does not sink.

In that regard - remember the engine is the heaviest thing, so you want to try an add the most flotation towards the stern

doesnt spray foam insulation absorb water?

Polyurethane foam like Great Stuff does not absorb water.

Great question. I've been wondering the same thing. I saw Tuff Stuff for sale at Home Depot last week for something like $3/can. I stopped and read the back panel, but I didn't see anything about water absortion.

Sweet. Thanks Quack! lol.. you posted while I was typing my reply and on the phone.

I had done some research myself as I'll be doing the same thing shortly. Great Stuff is closed cell so it will not absorb water. I've decided to use the the "big gap" version and it has much more expansion. It's also much less expensive than other mixture foam alternatives.

I'm not planning on removing any of the factory floatation. Just to help strengthen my new storage compartments & floor so I can use thinner wood to keep the weight down. We put a lot of gear in it when we go duck hunting. I'm thinking close to 1,000 pounds between hunters and gear. That a lot on a 20 hp outboard.

Nussy said:

I had done some research myself as I'll be doing the same thing shortly. Great Stuff is closed cell so it will not absorb water. I've decided to use the the "big gap" version and it has much more expansion. It's also much less expensive than other mixture foam alternatives.

Click to expand...

I've never seen the big gap stuff anywhere but on their site... does HD carry it in some secret aisle?

dyeguy1212 said:

Nussy said:

I had done some research myself as I'll be doing the same thing shortly. Great Stuff is closed cell so it will not absorb water. I've decided to use the the "big gap" version and it has much more expansion. It's also much less expensive than other mixture foam alternatives.

Click to expand...

I've never seen the big gap stuff anywhere but on their site... does HD carry it in some secret aisle?

Click to expand...

Yep, in my home depot its by the wood. It's in a black can. Also saw it at Walmart today by the paint.

ace hardware also has every kind of the spray foam great stuff. there is a pond and water sealer one. a fire one, big gap and regular. regular also comes in a even bigger can now

thats something i could also look into .. i could use it in my entire inside on the bottom and the lay a thin board as floor on top of that and i thing that will seal most of the tiny little leaks..

great post

I am not sure that it will work to seal leaks in the fashion that you are talking about. It would need to be in an enclosed volume when it was expanding so that it would expand into the leaking areas and not just cure in a pocket around it, leaving a seap/leak.

From my own use around the house, this stuff seems to last about 2-3 years before beginning to break down when exposed to the elements 24/7.

O **** thats no good i guess , but steelflex can do the most job that will be for just extra flotation to fill the gaps between the bottom and the floor . Well ce nothing is set yet . Icouldnt. Do anything so far its been pooring rain . And next week tuesday i hope it dont rain . Thats when i took my days off to start on this project .

My plan for this boat was to

1st fix all the loose rivets by welding
2nd coat the under floor area with rolled on bed liner (walmart 50.00 per gallon)
to prevent any future leaks
3rd re deck the boat with more under floor storage
4th fill any voids under the deck with foam sheet and spray
5th carpet or roll on bed liner floor area
not sure if I'm pulling out the live well yet

This is my game plan for fixing this old boat
trying to do this in a way so that it is still usable during the repair
I need to get some other projects out of the way first before I start on this

What are your suggestions?
likes or dislikes?

Damifinow fish