Concrete base on the (too small) oven stand

[McD]

Hi Helpful Forum,

I have a question about the concrete base on which to build the oven.

My oven stand is roughly 55X55 inches (140X140 cm), but I want to build a 42" oven. My installation sits in a corner with concrete walls to two sides, so I plan on making a corner installation. I will need roughly 10 inches / 25 cm of reinforced concrete hanging in the air.... What would be the optimal thickness of the concrete and what is the minimum requirement of the rebar?

Thanks in advance

[RandyJ]

I am not sure how thick to tell you to go. I would think 4"should be plenty, but mine is 6" there is not that much cost to go thicker if you are worried. Make sure that you build a nice grid of rebar to keep it reinforced. I did 1/2" on a 8"x8" grid and so far all is great.

Randy

[McD]

Thanks Randy. I was not really that worried, but just being an amateur, I needed to be sure no one would jump in and say that I had taken a disastrous path:-)

[Toomulla]

I am not sure how thick to tell you to go. I would think 4"should be plenty, but mine is 6" there is not that much cost to go thicker if you are worried. Make sure that you build a nice grid of rebar to keep it reinforced. I did 1/2" on a 8"x8" grid and so far all is great.

Randy

the important thing to remember is to place the steel in the top third of the concrete for the cantilever not the bottom which is where you place the steel for the span, personally I would go 6 inches purely for simplicity placing the steel, the tie bars should also be under the cantilever bars so that the steel is a high as possible

[JRPizza]

McD, the odds are most of you weight is going to be over your stand anyway. Since you are doing a corner build I would suggest making a full size layout (cardboard or whatever) representing at a minimum the dome and landing so you can see how big of a hearth you really need. Several of us have done the layouts in cad so that works well - there are some threads discussing how to do it using FreeCad. It will also help you decide if you just want to build a standard hearth to accommodate the vent (like I did) or build an extension/projection for the vent like others have done. Just depends on how much room you have and what look you like.

[RandyJ]

I would have to agree with JR that you will want to do a mock up of what you are thinking. Weather that is card board or cad doesn't matter much but you will need some kind of visual reference to help place every thing where you want it. So you don't end up scrambling to fix a situation you did not for see. Good luck and I am looking forward to seeing what you are building.

Randy

[McD]

I have a life-size cardboard copy that I was messing around with, but I did a quick CAD sketch just to get a different perspective and I can see that almost none of the weight is on the cantilever (only at the oven opening)
I might start my own thread for the project, but the actual oven building part will not take place before early spring. But at least it is covered:-)

[JRPizza]

Waiting until spring will give you plenty of time to fine tune what shape you want your hearth to be. There are lots of well documented corner builds here on the forum, hopefully some of them will help

[RandyJ]

That is a good idea to give yourself a few months to plan. I believe that I started mine about 2 months before I broke ground. I really like the corner builds. They take just a little more thought than some of the others to get it to all fit how you want. I look forward to seeing what you come up with.

Randy