Floatation

[Has Been]

After the talk on here about some of you guys redoing you boats , I talked w/ the spray foam guy the does the insulation on new homes. He tells me that the closed cell is what you want on boats . Said the chemical for that is pretty expensive. I asked him how much & he thought it to be around 300-400  for him to do it.

[LongLine]

I agree with you.  Did some research and even though the CG doesn't specify which, they do specify performance characteristics.  (Big time on life jackets.)  They also randomly test boats by going out & buying new ones and see what it takes to sink them.  I think all the foam sites I saw said closed cell should be used for floatation.  A few said that all foam will eventually absorb moisture but it takes much more time to soak the closed cell. 

 

Tom B.

(LongLine)

[SylvanTroller]

I did mine with two part expanding closed all foam from Jamestown distributors. You definitely want closed cell. Absolutely. I mixed both parts and then poorer in in. Be absolutely sure to block off any areas you do not want foam as it will expand and or run everywhere it can. (Trust me). I like the pourable foam much better than alternative ideas like pool. Noodles. Check out iboats forum there is a lot of conversations about this topic on there.

Sent from my iPhone using Lake Ontario United mobile app

[rolmops]

Spray foam is not the way to go. The Bayliners of the 1980s and 1990s were spray foamed and these days they are known as bilge liners. You can buy the right stuff to redo your foam at West marine and online. But it needs to be mixed in small quantities and poured while the outside temps are around 80 degrees. I've done a few and it's a pain, but it is the right way to go. Not only does it increase floatability it also strengtens the structure ,it lessens the flexibility, supports the floor and it dulls the sound of the water while on plane (aluminum boats).

It is possible to use the blue closed cell insulation boards from Lowes which is easily installed and replaced, but it does not help with structure. Besides ,it is just as costly as the poured material. If you decide to do it, lay some sort of plastic sheeting on the bottom and pour it inside the sheeting instead of right on the bottom.This keeps the water seperate from the foam. This is important because the main reason for closed cell failure is water freezing in small cracks and progressively destroying the cell walls. Once the water gets in the foam,your foam turns into ballast.

Any way you look at it, it's a messy job.

The good news is that, legally,  you do not have to use it in hulls that are over 20 feet long

[IRon]

http://univfoam.com/