Foam?

[jhk1959]

OK...Dumb question...do all boats have foam under the floor, or only some boats? Is the purpose of the foam to help the boat float, or to provide support? I'm not sure what I will find in my 1993 Wellcraft 18".<br />Thanks,<br />John

 

[fishingdan]

Re: Foam?

Foam, if done properly, will keep the boat (or remnants of) floating in the event of a disaster (flooding, capsize, hull failure, etc.). In normal situations, the hull does nothing to help the boat float. Flotation foam is required on all commercially built recreational boats. <br /><br />- If a hull breach occurs and the compartment is filled with foam, the foam will prevent water from filling the compartment.<br />- Foam is typically found under the sole of the boat and under the side decks (for positive floatation - boat stays upright if filled with water). <br />- Side benefits of foam are: sound insulation and in some cases, it can be a structural element that enhances the bonds from sole to stringers to hull.

 

[epresutti]

Re: Foam?

Kaptain,<br /><br />Like fishingdan said, hull displacement is what floats the boat. You could add foam til your are blue in the face and you won't significantly change the flotation characteristics (other than to add more weight).<br /><br />There are multiple types of foam, during my re-build I used "closed cell" (won't absorb water) phone between the stringers in the hull and left the bilge empty for fuel tank, misc parts. The phone I used will support 60lbs per cubic foot of foam, I used about 30 cubic feet, so about 1800 lbs of floatation. A little overkill for an 18ft boat.<br /><br />My reason for so much foam was I boat on the Gulf of Mexico, in the event of a catastrophic failure, I want some pieces (large pieces) to hold on to and I am hoping the whole thing doesn't sink to the bottom with the new motor. <br /><br />I also wanted to add sound deadening. When you start slamming some of the rollers in 3-5 ft seas it can be pretty jaring and loud.<br /><br />There is also a degree of structural support for the deck. I will be posting re-build pictures one of these days.<br /><br />Peace.<br /><br />Ed.

 

[Realgun]

Re: Foam?

Actually foam is not required of vessels over 20 ft in length and was not required before 1972.<br /><br />Foam is ther for two good reasons.<br /><br />The First and formost is it keeps the boat afloat in a catastrophe! IE hull breach , boat flips, etc.<br />Second is to provide some support and sound deadening to big open spaces.<br /><br />What you will find in a Wellcraft 18" is probably some batteries and an electric motor. <br />I think you mean 18'.