Corbels are not intended to support heavy weights.
Wood Corbels
and can support some weight like a small shelf with glass.
ArchPolymerTM
Corbels have the consistency of White Pine
GRG-NeoPlaster Corbels are not intended to be load bearing
Corbels are often used as decorative items that support the overhanging granite
countertops.
This is not a good use of a corbel as the granite is very heavy and
people inevitably will sit on
the
countertops from time to time.

We recommend the following for Granite Countertops that overhang:
1) Have your kitchen company install 3/4" plywood on the top of the lower
cabinet
everywhere the granite will be, thus under the granite.
This adds greatly to the support of the granite.
2) A 1-1/2" overhang bullnose or build-up on the front of the granite
should cover the 3/4" ply
3) You now have a place to screw the steel bracket
a) into the plywood
b) into the face gable of the front of the lower cabinet.
4) You can also embed the steel bracket into the lower cabinet gable and
cover it with a finished
face gable or filler
5) Now rout out the pattern of the bracket on the back of the corbel and
glue, pin or screw
it in place.
Without Prejudice the above message is intended only as a suggestion
for the betterment and
safety of
using heavy granite countertops. Remember Granite is stone and can
break under
variable conditions
and is effected by heat/cold variances.
Always use a
professional for installation.