9'' which is insufficient for proper knee space even when your counters are 42'' bar height.

Do a single level island. It's more useful as a workspace that way. Do hidden steel supports with at east 15'' of overhang. And allot a 30''x30'' space for a seated adult to occupy. Which impacts your aisle space. You need 60'' of space behind an island with seating if you are going to have frequent traffic passing there.

We were told anything over 10 inches requires support. The height of your ledge determines how much knee space is needed, here are the National Kitchen & Bath Association (NKBA) recommendations:

Table-height seating (30" high): 18" overhang

Counter-height seating (36" high): 15" overhang

Bar-height seating (42" high): 12" overhang

While lots of people on this forum sing the praises of the single level island or peninsula, I have had both and much prefer a raised counter. I know this is not on trend, but we just finished a kitchen renovation in February and removed the single level peninsula countertop and added a bar height counter. I hated seeing the sink and all the counter clutter from the family room. Yes, I live in my home and use my kitchen and I have counter clutter on a regular basis, I am much happier now that the raised bar hides most of it! You have to know how you live and what works for your family, sometimes that means bucking the trend

carra:

It depends.

I'd never install a 14" wide freestanding bar top over a 4 1/2" wall with a 9" cantilever without mechanical fasteners.

Supports can be very inconspicuous and improperly mounted stone can be dangerous.

It will be a raised bar - that's a done deal anyway and I've seen both and want the raised bar (mainly because the kitchen sink is in the sight line of the family room and the raised bar hides it)........ the actual overhang will be 10" (entire ledge will be 18") and according to my granite installer, anything 10" or under does not need supports. I have verified this with two people there. I have decided to add some 4.5" corbels, mainly for their visual appeal, but they will provide some support. My husband is an engineer and just can't understand how that much of an overhang does not require supports.

This post was edited by carra on Fri, May 30, 14 at 9:21

Your husband is correct. It's not just about the weight here. It's about the tiny little pony wall that is the contact support and will act as a pivot if some 300 pound burly guy puts that weight onto the overhang. Without support, that stone can come loose from the pony wall and crash down and crack someone's foot. And you'll be lucky if that's all it breaks. If someone's skull is in the path of that stone, you've got a death happening----one that is very easily preventable by installing the proper support. You will need corbels every 24"-30", or you will need steel stock screwed into the pony wall underneath the granite. There are a lot of options out there. The only option that shouldn't exist is no support at all. That's and injury and a lawsuit waiting to happen.

live wire oak - if my overhang is 10", are 4" corbels deep enough, or do I need deeper ones?

With only a pony wall of stlone's depth for weight to counterbalance instead of 25'' of a full cabinet depth's worth ,I'd personaly want at least 8'' of extension for the corbels. But 10'' won't be very comfortable to sit at. Your guests will want to sit sideways, and that will make them take up more width and aisle room than if you just went deeper on the overhang from the beginning. 12'' is the minimum suggested overhang, and with that 9'' corbels would be appropriate.

carra:

It's fine if you prefer the look of corbels, but they must be structural in nature. You can't just pin 'em to the drywall and I've seen that done too many times.