If this is a new home; why is this your problem to solve? Let the
builder
take care of it.


It was a second bathtub/shower that we didn't use until after our 1
year warranty period. Honestly, I would scared to let this builder
back into my home to sweep a floor, let alone fix something they did
poorly to begin with.


That said and assuming you still need help; here is an off the cuff
solution. Spray some minimally expanding foam into the hollow spout
through
the 1/4" gap, allow it to dry, trim off the excess and then caulk the
darn
thing. No I have never done this or seen it done but it might work.


I was thinking about that.

I am also thinking that part of the problem is the big hole around the
copper pipe that goes through the fiberglass tub, and so I'm thinking
that there might be some standard way to seal that hole so that water
cannot flow thru it if the seal around the spout fails, but I'm still
not sure what to use to seal the hole (gaps): about a 1" gap around the
pipe. I've never used plumber's putty. Does anyone know what the
typical way is to eliminate these prefabricated gaps in fiberglass
tub/shower units?