HI, I design all overhangs to at least 14". Sometimes they have corbels for extra support and other times flat steel rods are placed into the plywood substrate for the weight of the cantilevered overhang and then no corbel support is needed.

is there a rule on corbels in terms of when you need them and how many? We are doing an island in medallion rustic natural cherry and the simple corbels are $500 each - can I buy elsewhere but then I guess the wood won't match?

Wild Goose Carvings actually sell natural cherry corbels online at www.buycarvings.com They come in a range of sizes and styles. Take a look at their website and you can order shelf brackets immediately for far less money than you quote here.

overhang? We have just had an island constructed, I am waiting for the counters to be installed. I would like a 10 inch overhang. The base cabinets are 18 inches (there are door panels on either side of 18 inch cabinets, which adds an inch overhang on the sides as well + 1 inch overhang) equals 20 inches of supported granite. Is the 10 inch overhang at risk for breaking off or not being supported in some way?