Be aware that animals (beavers, muskrats) will chew the "stryofoam" into
little pieces which will than float across your entire lake. A local nature
area used "styrofoam" blocks to make floating sidewalks. They have since
switched to prison labor with tiny aqaurium nets to fish the stuff out of
the virgin wetlands as it does not decompose.

"toller" wrote in message
...
My neighbor threw out a 6' diameter hottub cover, presumably because the
fabric covering had a small cut in it. It is entirely styrofoam.

I was thinking of using it either as a swimplatform at the lake, or as
floatation for a wood swimplatform. The manufacturer recommends against
it; although the covering is nominally waterproof (well, after I patch the
cut) the styrofoam will eventually absorb water and become useless.

Is that true? Styrofoam is used for boyancy in boats and it doesn't
absorb water, but maybe they waterproof it somehow. (wouldn't you think a
hottub cover would be waterproof?)