The Americast tub is really a steel tub with a resin backer. The flex is not a problem. It will last and last. Terry
: No one will respond, not even American Standard, sure am glad I bought their product! I had an Americast Princeton Tub installed about 5 months ago, contractor said no morter mix was needed underneath the tub since it was not fiberglass, it would not flex or give, but everyday, I feel it under me give a little, I have even spoke to a few plumbers, not too many people have even worked with these tub to know enough about them, It seems pretty secure, but I do not want to wait until its too late, I can always shoot some expandable foam under it from the back, but the can tells me, not for tub surrounds. Help!!!!