In alt.home.repair
tofuboy wrote:

Around indoor pools I see this rubbery grout-like material that's put
inbetween the joints of the concrete slabs to keep the water out.
Where do I get this stuff? What exactly is it?

It is not to keep the water out primarily. It is there to allow the deck
to move and expand without pushing against the coping. If it isnt' there,
the movement will begin to crack and pop tiles like my pool did because it
wasn't built properly. I now have Deckoseal after $7500 worth of
renovation OUCH!