What does the lbs. density in expandable foam mean?

Question

I’ve been piecing info on building pontoon boats and wanted to know what the density meant. On one hand I think a higher density would be less buoyant, and on the other I don’t actually know what I’m talking about so your input is greatly valued. thanks.

In: Chemistry

Answer 1

It mean how much it weighs per block of the stuff. Usually it’ll say something like 5 lbs/ft^3, meaning a 1’x1’x1′ cube weighs 5 pounds.

The density of water is about 62 lb/ft^3, so anything LESS than that will float. The less dense, the better.