Re ][<en's answer:

>Glass Fiber Reinforced Concrete (GFRC) is correct.

Right.  (and GFRP = ....polymer.  Some other countries just call it FRC.)

I have seen cornices made of GFRC, replicating stone or terracotta.
Virtue is that the sun's UV doesn't attack GFRC like it can plastics,
yet fabrications are thinner than steel reinforced concrete
considering the coverage you need for weathering.  I have heard of
weathered GFRC getting a touch of the "fuzzies" when the fibers start
prickling out.

We used GFRC as the back-up arch for the replicated Guastavino tile
over the Grand Central taxi entrance.  Original vault was the
historic Guastavino 3 tile built up system since the original could
be laid up from overhead before the elevated roadway went into place.
GFRC allowed us to replicate the shape, work quickly and provide a
sound back-up to standard tile, working entirely from below.  But
don't get the idea that GFRC is really lightweight.  Relative to
steel reinforced precast, yes, but at 1/2, 3/4 and thickened toward
reinforced perimeters, it can still get pretty heavy.

The Rev'

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