Re: do i need to use foam?
This foam issue has been beat to death over the years......the bottom line is the old style foam (open cell) actually can and will absorb moisture from the air, collect it and not release it. Many boats have rotted as a result. Closed cell foams have their own issues, regarding trapping moisture between the foam and the structure, if there is no path for drainage. I live about 2 miles from a factory that builds boats for 3 different brand names, and my employer is involved in supplying them some parts...so I get to talk with them a lot. As they put it, boats in the 70's, 80's and 90's had the foam installed because the USCG required it. The testing required to satisfy the USCG was often expensive and ruined one boat for each certification. They were fully aware the foam would only last 2 or 3 years before it absorbed enough moisture, added weight and actually made the boat dangerous. Area's with high humidity, like the S.E. USA, life span was shorter. But, they had no choice per USCG. As a person rebuilding a boat, you have a responsibility on a 20' or less boat to make sure it still floats if it gets swamped. Foam is not required....adequate 'flotation' is required. Everything has been used from ping pong balls to 2 liter pop bottles. "Technically", if you do not replace the flotation with the exact type and quantity of what the manufacturer used, the USCG could require a certification test. (Swamping the boat, loaded to capacity in a controlled environment, like a pool.) However, they have never been known to require consumers to certify their own work in this manner. The issue could arise later on, as mentioned above, in the event of a sinking. So a basic rule of thumb on flotation, if you want to avoid the crappy foam.....make damn sure you use more than enough flotation of whatever kind you choose. (On a restoration I did a few years back, we calculated the foam Reinell used under the deck, and were able to install foam under the gunwales that exceeded the amount the factory installed. This prevents future rotting issues, it is easy to inspect and replace if needed, and by building in air pockets under the deck with bulkheads glassed in, added even more to the floatability.) Now...if you leave out the foam on an 18 foot boat, be aware that it can go down in less than 60 seconds from a good hull breach. Nobody is going to inspect your work, unless maybe if someone dies.....so think about it. If you saved some money on car repair and left out a passenger air bag, do you think someone would be coming for you if a passenger died as a result? Both civilly and criminally I suspect......
