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.