Help with Counter over hang questions?

[ride92]

I know this about the garage but you all seem pretty knowledgeable about all things construction, home and garage so I'm hoping someone can help answer my questions.

reviewing the drawings for the new house and the we have a large center island in the kitchen that over looks the great room/living room. We plan on doing Quartz counter top. The plans right now are roughly 98"x54" with a 16" overhang on the long side and a 12" over hang on the one short side. To support the overhang the builder is going to use T-brackets but they are also saying that they need to build a 12" thick wall just behind the cabinets to support everything. If we went with the standard 10" over hang on the 2 sides it would a 2x4 wall. The problem is because of that super thick wall it pushes the counter width to 54", we were originally thinking about 48-50 inches wide, and that extra width makes the seating area of the counter really close to where the living room starts.

The builder is saying that they have to do a 12" thick wall and I'm just not fully buying that. That extra thick wall is going to cost roughly $900! Should I be pushing harder for them to find different brackets or have them do just a 2x6 wall or something? It seems like over kill especially for quartz which is much stronger then Granite. Any advice is appreciated.

 

[readhead]

I have built lots of brackets for counter tops over the years and have never seen anything over a 2x6 wall.

 

[ChaseDE]

Yeah that sounds like major overkill. We have a standard kitchen island cabinet that is probably 5' x 3' then a 1.5" thick granite top on it that hangs over the backend like 12" or so with >0< support at all.

How thick is the quartz?

 

[blacksporty]

I have a 16" overhang on my island, with no supports with granite on top of a plywood base on top of the kitchen cabinets.

 

[TRWham]

Just to be clear, are you saying the top is 98" by 54" including the overhangs? How large are the cabinets in the island? Are there any cutouts in the stone (sink or cooktop)?

https://originalgranitebracket.com/

I found these guys when doing a project where the client wanted an 18" overhang. Any overhang more than 12" or so needs support (10" is pretty standard). We ended up using large angle brackets set into relief slots in the cabinets and screwed to the inside. There was no knee wall of any kind in that case.

However, if I understand the layout, I think the builder is concerned about how this top will balance rather than just how to support the load, and I might agree with him. The weight of the cantilevered stone plus anything on it will impose a moment (rotating force) that will pull the cabinets over. Better brackets or corbels will not eliminate it, but a wider wall moves the balance point away from the overhang. Any cutouts on the other side just make the balance that much worse. Have you considered adding posts at the corners (and perhaps middle as well) of the overhang? Those will resist the rotation.

 

[zoepop]

I would talk to the granite installer to see what they recommend. I'm in high end custom homes all day everyday, 12" usually you can get away with nothing. A lot depends on the type of stone. 16" you should have some support. When they want to do it so you don't see it you can take flat stock steel and rabbit it into the top of your cainets. Go from the front of the cabinet to 1" shy of your overhang

 

[glentre]

May not be a solution in your case but here's what I did to eliminate the need for those ugly corbels or brackets. Any appreciable overhang with small kids around and no support is asking for a broken top.

Glen

 

[Handyfarmer]

steel?, build a framework of steel and then cover the frame work with wood,

amazing what the strength of a properly designed steel frame work has,

carpenters think wood not steel, or most of them, and most steel fabricators do not think wood,

 

[Falcon67]

We have a peninsula that is about 65" x 48", 3mm granite with a 16" overhang on the long end and 12" on the short side. I made some brackets from old connecting rods to support the over hangs. The whole slab sits on built in place cabinetry, paper thin walls. No problems.

 

[ride92]

We have a peninsula that is about 65" x 48", 3mm granite with a 16" overhang on the long end and 12" on the short side. I made some brackets from old connecting rods to support the over hangs. The whole slab sits on built in place cabinetry, paper thin walls. No problems.

This is exactly what I am wanting to do! But add a 2x4 or 2x6 pony wall at the back to the cabinets for added strength.

 

[ride92]

Just to be clear, are you saying the top is 98" by 54" including the overhangs? How large are the cabinets in the island? Are there any cutouts in the stone (sink or cooktop)?

https://originalgranitebracket.com/

I found these guys when doing a project where the client wanted an 18" overhang. Any overhang more than 12" or so needs support (10" is pretty standard). We ended up using large angle brackets set into relief slots in the cabinets and screwed to the inside. There was no knee wall of any kind in that case.

However, if I understand the layout, I think the builder is concerned about how this top will balance rather than just how to support the load, and I might agree with him. The weight of the cantilevered stone plus anything on it will impose a moment (rotating force) that will pull the cabinets over. Better brackets or corbels will not eliminate it, but a wider wall moves the balance point away from the overhang. Any cutouts on the other side just make the balance that much worse. Have you considered adding posts at the corners (and perhaps middle as well) of the overhang? Those will resist the rotation.

I agree that the 16" over hang is going to need support. I actually sent links to the Original Granite Brackets to the builder in hopes they would be able to either get those L-shaped brackets or something similar from their vendor. If I am doing my math correct a base cabinet is 24" deep, add a 2x6 wall to the back side of that that is finished to a 6-1/2" width and that is 30.5". Account for a standard 1.5" overhang on the front side of the cabinets and that leaves 16" of overhang on the back side if using a 48" wide counter top, which is just about what I'm wanting. 32/48=.6667 or 66.7% of the countertop will be supported by the base cabinets. I think that is plenty sufficient to not have an issue with it tipping over or impose a moment where the counter would rotate. Am I correct in thinking that?

 

[readhead]

Exactly right. But I would still install some brackets under the overhang. Some 1/2" x 2" brackets turned down on the cabinet side of the wall will stiffen the overhang.

 

[Toolfool]

I agree that the 16" over hang is going to need support. I actually sent links to the Original Granite Brackets to the builder in hopes they would be able to either get those L-shaped brackets or something similar from their vendor. If I am doing my math correct a base cabinet is 24" deep, add a 2x6 wall to the back side of that that is finished to a 6-1/2" width and that is 30.5". Account for a standard 1.5" overhang on the front side of the cabinets and that leaves 16" of overhang on the back side if using a 48" wide counter top, which is just about what I'm wanting. 32/48=.6667 or 66.7% of the countertop will be supported by the base cabinets. I think that is plenty sufficient to not have an issue with it tipping over or impose a moment where the counter would rotate. Am I correct in thinking that?

I've been doing custom kitchens for over 34 years (see my thread) and have installed islands in this manner many times. Your builder may be thinking you want the overhang section raised , in which case it would need a wider base.

 

[Radix2]

a very strong way to support overhangs that I use is to space the island cabinets by 3/4" and then you can use a shear panel between the cabinets to support the counter top. Typically all that shows is a thin wood or metal bracket attached or part of the filler panel, but now you have much more strength than just loading the cabinet box directly.

I dont understand the need for any thickness to the pony wall unless you are trying to cantilever a mult height counter off of it., even there are plenty of ways to properly anchor a pony wall that it would never need to be more than a two by.

 

[tinmanwpk]

We have a peninsula that is about 65" x 48", 3mm granite with a 16" overhang on the long end and 12" on the short side. I made some brackets from old connecting rods to support the over hangs. The whole slab sits on built in place cabinetry, paper thin walls. No problems.

Nitpicking, but I presume you mean 3 cm, not mm.

 

[Brian_WK]

I've been doing custom kitchens for over 34 years (see my thread) and have installed islands in this manner many times. Your builder may be thinking you want the overhang section raised , in which case it would need a wider base.

So is this a 2 level island like countertop and bar top heights? That how I was reading between the lines in the original post.

Brian

 

[ride92]

The counter is not 2 different heights, it's all on the same level. And yes I meant 3cm not mm. I think it's actually 1.5" thick or 1.25" thick, can't remember.

Anyhow, after much debate and measuring and arguing with the builder we have agreed to go down to a 14" overhang on the long side and a 12" overhang on the one short side. This setup doesn't require the use of any support brackets and should give us a final counter top measuring 98x44 or so. I'm waiting to hear if that is correct or not from the builder. I drew the counter up in autocad and that's roughly the measurements I got so It should be pretty close.

 

[TRWham]

The counter is not 2 different heights, it's all on the same level. And yes I meant 3cm not mm. I think it's actually 1.5" thick or 1.25" thick, can't remember.

Anyhow, after much debate and measuring and arguing with the builder we have agreed to go down to a 14" overhang on the long side and a 12" overhang on the one short side. This setup doesn't require the use of any support brackets and should give us a final counter top measuring 98x44 or so. I'm waiting to hear if that is correct or not from the builder. I drew the counter up in autocad and that's roughly the measurements I got so It should be pretty close.

3 cm is about 1 3/16".

Okay, I still would not do this without brackets at least. The issue is not one of supporting the weight, but of preventing the stone or the entire assembly from tipping. I know it looks like you have a 2:1 ratio of supported to unsupported stone, but the stone is only held down by gravity, and as soon as you put some weight on the overhang (like someone sitting on it), your calculations are all useless. The homeowner (or his lawyer or insurance company) will come looking for the builder when that happens. The brackets can be completely hidden to anyone not lying on the floor and I would prefer to be cautious.

It is your kitchen and you can do as you wish, but be cautious about second guessing your builder. He doesn't want 600 pounds of granite to fall on you, and I imagine you don't either.

 

[ride92]

The builder was pretty unmoveable on the whole bracket install thing. They said with a 14" overhang they don't require a bracket support. I didn't fight for them to do that, they just offered it up.

 

[Falcon67]

Nitpicking, but I presume you mean 3 cm, not mm.

One of them meters LOL

Brackets, and a healthy rendition of "Hey, don't swing on that! Whadda think you're doing??!?"

 

[tjpavlov]

Check out Fastcap. They make something called the stealth speed brace that might help you out.

 

[Lelandwelds]

a very strong way to support overhangs that I use is to space the island cabinets by 3/4" and then you can use a shear panel between the cabinets to support the counter top. Typically all that shows is a thin wood or metal bracket attached or part of the filler panel, but now you have much more strength than just loading the cabinet box directly.

I dont understand the need for any thickness to the pony wall unless you are trying to cantilever a mult height counter off of it., even there are plenty of ways to properly anchor a pony wall that it would never need to be more than a two by.

This is slicker then screwing ugly corbels to the wall.

I have 14.5" and ugly corbels. (I had a high school buddy break some public space granite counter getting luck once. And yes, she was a big framed girl. ) I like the extra reinforcing.

I wish I had thought of this.