We're thinking about using 2-part flotation foam in the front and rear flotation chambers.
Other than cost (which is minimal), is there any good reason not to?
We're thinking about using 2-part flotation foam in the front and rear flotation chambers.
Other than cost (which is minimal), is there any good reason not to?
Great question. There are definite pros and cons to adding two-part expanding polyurethane foam to the flotation chambers.
The most obvious pro is virtually indestructible flotation. A boat could be pummelled onto a reef or involved in a significant collision and still emerge cracked, broken, and bruised—yet with substantial buoyancy remaining.
The biggest con, however, is weight. The foam adds significant mass, and that can increase over time if a flotation chamber ever cracks and allows water ingress (the foam can absorb some water). Even without any absorption, you’re looking at roughly 2 lb per cubic foot, which can easily add more than ten pounds to the boat.
Personally, I’ve never added foam to the chambers, as I feel the risk of structural damage is relatively low. Unless the boat is involved in an accident, a catastrophic failure is unlikely. Even if there were a small crack or pinhole that went unnoticed, it’s improbable that much water would enter before recovery. And when cartopping or carrying boats, I’m usually thinking about how to make them lighter rather than heavier.
That said, foam does add a small margin of additional safety. Unless… it slows you down just enough that you miss making it into harbour before the storm hits. 😉
And that's exactly why I posted! Thank you for the insight and the quick reply, Colin.
Since our boat will be on inland lakes only, we'll pass on the foam.
