# Kitchen Island Overhang Support



## sethmc93 (Aug 12, 2020)

Hi,

I'm building a kitchen island with a wood countertop and a 16" overhang for seating on two adjacent sides. I plan on using these iron supports under the overhangs. The portion that concerns me and that I'm here to ask about is the corner. Will the iron supports be sufficient support for the corner between the two overhang sides?

Please pardon my poor drawing abilities. The inner box is the base cabinets / support wall and the outer box is the wood island top. The squiggly lines are the iron supports from the link above.










Any help/advice is greatly appreciated, thank you!


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## DrRobert (Apr 27, 2015)

I would say consult the granite company.

Personally I would want a support 45° from the corner, no matter what they say . There may be implications on the cabinetry doing this, so plan ahead on the design.


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## sethmc93 (Aug 12, 2020)

DrRobert said:


> I would say consult the granite company.
> 
> Personally I would want a support 45° from the corner, no matter what they say . There may be implications on the cabinetry doing this, so plan ahead on the design.


It's actually a wood countertop so no granite company to consult on this one unfortunately!


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## DrRobert (Apr 27, 2015)

sethmc93 said:


> It's actually a wood countertop so no granite company to consult on this one unfortunately!


What type of wood? There are factors to consider.


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## sethmc93 (Aug 12, 2020)

DrRobert said:


> What type of wood? There are factors to consider.


Still open on the species of wood, I was considering white oak or potentially cherry.


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## Rebelwork (Jan 15, 2012)

There is always support on a 16" overhang.only problem with overhang is eventual droops. Are you doubling up the thickness?


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## sethmc93 (Aug 12, 2020)

Rebelwork said:


> There is always support on a 16" overhang.only problem with overhang is eventual droops. Are you doubling up the thickness?


Yeah, there will definitely be supports, I just wasn't sure if the supports in my sketch would be adequate for the corner area. I was planning on a 1.5" thickness but that can certainly be modified if necessary.

Do you think there would be drooping between the supports (about 15" spacing between them) or are you referring to the corner area?


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## Rebelwork (Jan 15, 2012)

The pictures shows you have plenty, just dont sit on the edge


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## yomanbill (Jul 7, 2020)

It depends on what type of wood you use and the direction of the grain. Of course, solid wood will be weakest with bending forces parallel to the grain. If you use a veneer plywood, this will not be as much of a concern. 
If you mount the brackets you reference according the the diagrams and photos the manufacturer provides, there should be no strength problem with the brackets. However, if you plan to mount them to the face of the cabinet, the short leg of the bracket will certainly be too short. Find a bracket where the leg mounted to the cabinet is about the same length as the horizontal leg. 
Without a structural analysis, I would be inclined to have a support bracket at a 45 deg angle at the corner; just my gut feeling. You might also consider either rounding or clipping the corner to reduce the overhang distance to the same 16" or less. I think I would use a rounded corner with a 16" radius along with an angled bracket.


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## sethmc93 (Aug 12, 2020)

yomanbill said:


> It depends on what type of wood you use and the direction of the grain. Of course, solid wood will be weakest with bending forces parallel to the grain. If you use a veneer plywood, this will not be as much of a concern.
> If you mount the brackets you reference according the the diagrams and photos the manufacturer provides, there should be no strength problem with the brackets. However, if you plan to mount them to the face of the cabinet, the short leg of the bracket will certainly be too short. Find a bracket where the leg mounted to the cabinet is about the same length as the horizontal leg.
> Without a structural analysis, I would be inclined to have a support bracket at a 45 deg angle at the corner; just my gut feeling. You might also consider either rounding or clipping the corner to reduce the overhang distance to the same 16" or less. I think I would use a rounded corner with a 16" radius along with an angled bracket.


I plan on having the grain flow in the direction of the longest edge. I also plan on installing the brackets the way shown on their website, not attached to the outside of the cabinets.

I think you're right about rounding it to a 16" radius, that sounds much better structurally and probably better aesthetically as well. Now, getting an bracket mounted diagonally without interfering with the drawers might be challenging.

Thank you for the input!


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## yomanbill (Jul 7, 2020)

To not interfere with the drawers, would it be acceptable to have an external angle bracket just at the corner? The same company offers several "shelf brackets" that might work at just the corner.


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## sethmc93 (Aug 12, 2020)

yomanbill said:


> To not interfere with the drawers, would it be acceptable to have an external angle bracket just at the corner?


If totally necessary I think it would be okay, it would definitely be preferred to keep the hidden support style but function obviously comes before form.

You think even with the material removed by a 16" radius another support would be necessary? The supports are rated for 16"-20" spacing on center.


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## DrRobert (Apr 27, 2015)

You’ve got a challenge with the miter I think. The are complicated issues involving a long miter and wood movement. I’ve never gotten my mind completely around it. It seems to me the issue would be the longest part of the miter wanting to pull apart, and if that is fastened securely, what will happen? I could see a situation where the whole countertop woukd want to pivot?

I would definitely spend some time researching this.


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## sethmc93 (Aug 12, 2020)

DrRobert said:


> You’ve got a challenge with the miter I think. The are complicated issues involving a long miter and wood movement. I’ve never gotten my mind completely around it. It seems to me the issue would be the longest part of the miter wanting to pull apart, and if that is fastened securely, what will happen? I could see a situation where the whole countertop woukd want to pivot?
> 
> I would definitely spend some time researching this.


I'm not sure I follow, where would there be a long miter? It's basically a large rectangular tabletop with the grain running in the direction of the longest side and then one corner rounded off to a 16" radius.


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## DrRobert (Apr 27, 2015)

Disregard, I misinterpreted the drawing. I thought it was a bar separate from countertop.


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## Bob Bengal (Jan 2, 2021)

A possible alternative to the brackets:








Steel tubes across the tops of the cabinets. Professionally built, 23 years old, Corian top.


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## Frost (Sep 24, 2018)

I think you'll be fine. You do need to pay attention to wood movement, Make sure your brackets have slotted screw holes so the top can come and go. Might mean adding a wood piece to the top of the bracket so you can slot the hole, or enlarge the hole in a metal bracket somehow. Design the top so brackets are hidden, might mean doubling up the edges just keep grain running the same direction.


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## Tool Agnostic (Aug 13, 2017)

We have a kitchen peninsula counter with a 15 inch long cantilevered overhang and no external supports. The granite slab is supported internally with 3/4 inch Baltic Birch plywood. It was installed by a contractor, not me. So far, it has worked well.

We had a discussion with the contractor about the design. All of us were concerned that such a long overhang might require corbels or other supports, which we did not want. 

The contractor felt that the unsupported overhang design exceeded the maximum recommended, but felt that it would work as long as we used the strongest plywood we could find, and promised that nobody sits on the counter edge itself. So far, so good. See the photos.

Important Notes: 
Our counter is granite, not wood. 
Our counter runs along one side only and has no corner overhang. 

I would be concerned that 16 inches on 2 sides with that unsupported corner would be too much for our solution, but I wanted you to see what we have in case it stimulates other ideas.


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## yomanbill (Jul 7, 2020)

I think that, because of the direction of the wood grain, the shorter end overhang will be stronger than the long side. With the rounded corner and the bracket supports as shown, you will probably be OK without the diagonal bracket. My gut says that you should do it to be safe, but my brain says "naw, you don't need it" .


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## Steve Neul (Sep 2, 2011)

What you have drawn looks alright to me except maybe you have more brackets than needed. It appears the island top is around 5' long, I think a bracket and each end and one in the middle would be sufficient. If the top is 1 1/2" thick probably one bracket on each end would be enough.


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## Jar944_2 (Oct 30, 2020)

DrRobert said:


> You’ve got a challenge with the miter I think. The are complicated issues involving a long miter and wood movement. I’ve never gotten my mind completely around it. It seems to me the issue would be the longest part of the miter wanting to pull apart, and if that is fastened securely, what will happen? I could see a situation where the whole countertop woukd want to pivot?
> 
> I would definitely spend some time researching this.


Unrelated to the OP'S question, but the angle of a miter (in wood) changes with expansion and contraction (because the length of the miter stays the same, while the width fluctuates)


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