"over time" ??? How much time?

It is a safety issue, but most or us aren't going to spend weeks or months
depending on it.

Sometimes the difference is not in the material but in the documentation and
"approvals."

Roger

http://home.earthlink.net/~derbyrm

"Brian Nystrom" wrote in message
news:E9xKe.5643$lK2.4843@trndny01...

keith wrote:
Just a quick question. Is polyurethane buoyancy/flotation foam in
aerosols the same as the polyurethane foam sold at builders merchants
for sealing voids and cracks etc? The reason that I ask is that my local
chandlery has aerosol foam that
looks about the same if you read the ingredients etc on the tin, but
the builders is cheaper.

Floatation foam is generally a two-part foam specifically made to be
waterproof. Most foams used in construction will absorb water over time.
Considering that buoyancy is a safety issue, it doesn't make sense to risk
using sub-standard or inappropriate products.