Cantilevered oven landing

[jagizzi]

I am wondering whether or not it is safe to assume that the hearth pad could be cantilevered a bit. I am trying to move the oven landing further under the porch roof. See attached drawings.

Someone kindly posted this design in the Google Sketchup warehouse and it is perfect for what I would like to do. The front of the hearth pad is cantilevered 2', and the sides are cantilevered 1'.

Can this safely be done using the standard techniques described in this forum?

Note that I will not have the roof support beam going through the hearth slab. It is more likely that I will either round the corner, or cut it off such that it clears the beam.

I would guess that a guy could incorporate some type of steel support on the edges of the cantilevered portion. Possible some angle iron that extends out to the extents of the overhang. Would these keep the concrete from cracking?

Advice is appreciated.

[Alter ego]

Re: Cantilevered oven landing

Jacizzi,

The slab holding up my oven is cantilevered and it hasn't fallen down. The front overhangs by 440mm and the sides & back by 260mm. I did this as I wanted to make the base structure as small as possible so that it didn't dominate the back yard.

The hearth slab is 100mm thick and I put 4 x 12mm steel reo bars in the slab across the opening and further reo in the top part of the slab to act as a cantilever in the overhang. I'm sure I over did the amount of reo in my slab but I?m confident that I could always use the wood storage area as a bomb shelter should the need arise. Attached are a few pics of the overhang.

Paul

[dmun]

Re: Cantilevered oven landing

This builder has his oven on a twelve inch pedestal. No reason it can't be done.



As Paul says, rebar is your friend in these situations.

[ralogan55]

Re: Cantilevered oven landing

jagizzi,

You should be alright with the 1' cantilever on the sides with no problem. The 2' cantilever with no vertical support is a bit trickier.

If the cantilevers are 5.5" thick (a fair amount of weight) I would use a heavy rebar schedule in the 2' portion and don't let anyone stand or sit on it. If you're in doubt I would have it engineered.

I have a 14" granite (1" thick) overhang in my inside kitchen and the granite shop wouldn't warranty the stone for any more overhang without corbels or other support. I know 1" of granite isn't 5.5" of concrete, but I'd think with the extra rebar you'd be okay.

[jagizzi]

Re: Cantilevered oven landing

Hey folks,

Thanks for all the feedback. I had a contractor over today to talk about the porch that this will be attached to. He's doing the porch, I'm doing the oven ;>)

He agrees with the overall general consensus expressed here. Easily done with the right rebar. He's talking 1". I would order it cut to length and bent.

Movin' on to the next phase then and counting this as a design feature.

Thanks,

Jim

[ralogan55]

Re: Cantilevered oven landing

Jim,

It's not just the rebar diameter, it's the spacing (but I'm sure the GC told you this or maybe you already know). The closer the spacing the smaller the rebar, but with 5 1/2" of thickness 1" rebar has plenty of room. Movin' on....

Rick