Maximum Overhang For Granite Countertop

Final determination on bracket requirements and spacing should be recommended by your fabricator.

Maximum overhang for granite countertop.

According to the marble institute of america you can safely overhang granite that is 1 inches thick up to 10 inches without support. Yes you can extend the overhang on a kitchen island countertop. So to clarify the maximum overhang is the lesser of 2 3rd or 12 inches. The marble institutes 12 inch guide line may lead someone to believe that it is ok to have 12 inches of overhang when in this situation it would immediately fall off the wall and potentially injure anyone with feet in the path of the falling granite.

Most granite fabricators will recommend support brackets on overhangs over 12 however solely based on the overhang amount. Nkba standards recommend 12 quot. Overhangs greater than 15 require the installation of corbels. However the cantilevered portion cannot be more than 1 3 the total width of the countertop.

Of overhang for 42 quot. Bar height seating 15 quot. High counter seating and 18 quot. The corbels must be designed to support the weight of the countertop and be mounted to studs.

Without any additional support solid surface countertop overhangs cannot exceed 6 engineered stone cannot exceed 14 and granite overhangs shouldn t be more than 10 without additional supports. Corbels can support no more than 24 of the overhang. So we are ok on the first criteria but we exceed the 1 3 criteria by four inches. If you only have 6 inches of stone on top of a wall cap then the maximum safe overhang is 2 inches following the 2 3rds rule.

The marble institutes 12 inch guide line may lead person to believe that it is ok to have 12 inches of overhang when in this situation it would immediately fall off the wall and potentially injure anything with feet in the path of the falling granite. The allowable overhang with no additional support is no more than 1 3 of the depth of the countertop and not to exceed 15 total. The standard overhang for granite countertops is 1 inches 12 inches for an island just like the standards in general. Once your countertop overhang exceeds these numbers it will require additional support through corbels base cabinets or knee walls.

Can you extend the overhang on a kitchen island countertop. However the cantilevered portion cannot be more than one third the total width of the countertop. According to the marble institute of america you can safely overhang granite that is 1 1 4 thick up to 10 without supports.