Concrete slab question

[fxpose]

Re: Concrete slab question

Here are a couple more pics. I poured that 5 x 8 slab just yesterday, just in time before we get some rain tonight and into the weekend.
I also tapped into and ran a copper line under the slab to supply water to the oven & bbq area.

[ThisOldGarageNJ]

Re: Concrete slab question

how many more sections till you get to where the oven goes ?

[fxpose]

Re: Concrete slab question

how many more sections till you get to where the oven goes ?

Well, I still have perhaps another 100 sq/ft to go to reach the oven area (plus another 300+ sq/ft will eventually be poured to finish the entire patio) but since I know exactly where the oven is going I can start building up the oven foundation and bring it up about 5 feet to elevation where it will meet with the patio. But meanwhile I need to continue expanding the patio outward and sideways so my wife won't question my time being spent on that strange looking structure (round oven stand).

[ThisOldGarageNJ]

Re: Concrete slab question

Just tell her it's an enclosed fire pit ...

[Neil2]

Re: Concrete slab question

"bring it up about 5 feet to elevation where it will meet with the patio. "

When you get there, you may want to consider "isolating" the patio slab from the oven foundation. The loading and movement will be different enough that you will get cracking if you connect the patio slab to the oven slab. One way of doing this is to put a 1/2 inch felt band between the two.

[fxpose]

Re: Concrete slab question

Yes Neil, I will definitely isolate the entire foundation from the patio slab. I've seen this mentioned elsewhere here on the forum about isolating these slabs. And I like the idea of using the felt band. Thanks!

Oh, and another thing. ... The reason I like your sonotube stand is that it doesn't dominate the landscape. My oven located at the end of the patio, down a sloping hillside with virtually no landscaping behind it may look huge and out of place, sitting in open air, I basically want the footprint to be as small as possible. This is why I'm leaning towards a round stand which is far easier for me to erect than going the sonotube route.

[Neil2]

Re: Concrete slab question

"I'm leaning towards a round stand which is far easier for me to erect than going the sonotube route."

Based on the concrete work you have done so far the sonotubes should be dead easy for you. Just prop them firmly in place, drop down a couple of 1/2 in rebar and then fill with concrete. They can either sit on a foundation slab or be a continuation of below ground piers 4 feet deep or so.

[fxpose]

Re: Concrete slab question

They can either sit on a foundation slab or be a continuation of below ground piers 4 feet deep or so.

You got me thinking there again ...

I would imagine planting them on a foundation slab would be a lot less labor intense than digging out several feet of hard clay for each tube... Although aesthetically I would prefer the look of individual full length concrete columns jutting up from the ground below.

I already had one oven design in mind with the round stand. Now, that design may not look right with sonotubes underneath. We'll see...

[metalmaster]

Re: Concrete slab question

something like this

[Archena]

Re: Concrete slab question

How is digging the foundation that much easier than the holes for the tubes?

My suggestion - rent an auger.

[fxpose]

Re: Concrete slab question

How is digging the foundation that much easier than the holes for the tubes?

My suggestion - rent an auger.

With a 2 person auger I'm sure it's an easy task. I might just do that.
Digging for the foundation slab I don't have to dig as deep into hard packed clay.

[fxpose]

Re: Concrete slab question

how many more sections till you get to where the oven goes ?

Here's another pic with a better perspective of where the oven will go. It will be located about 8 ft to the right of where the cement mixer is, where the palm tree used to be, and brought up to the same elevation as the slabs in the foreground.

[Neil2]

Re: Concrete slab question

Hard packed clay ?

Dig three holes. Space so they support your slab with center about 1/3 of the way in from the outside on the radius.

Use a hand held post hole digger (the "clam shell" kind) and rent an impact driver with a long (5 ft) bit. This will get you down fairly quickly. Dig a six to 8 inch diameter hole. Bell it out at the bottom as best you can. You don't need sonotube down the hole. Simply place and support a pair of 3/8 rebar in the hole and to the height of your sonu tubes plus 12 inches or so. Fill with concrete to six inches or so below the final finished grade.

Wait to set for a day or so. Widen the top so you can place the sonotubes down a bit below finished grade. Support the sonotube well. I suggest 7 to 8 inch diameter tubes. Fill them with concrete. Tap the sides with the handle of a hammer. Rapid taps - you should be able to see the bubbles appear at the top near the edge of the sono tube. The tapping is to minimize the number of voids that will appear. Don't worry to much about this as you wil almost always get some anyway and you can parge the finished concrete later if the appearance is an issue.

The top 12 inches or rebar is to bend down and tie to your structural slab rebar. Wait at least 3 day before bending. Keep the out side of the sono tube wet for at least 7 days. See also:

http://www.fornobravo.com/forum/f21/flying-saucer-3033.html

[fxpose]

Re: Concrete slab question

Thanks Neil, that is certainly doable. I will give the sonotubes some serious thought before deciding which way to go. I love the look and simplicity of the sonotube stand.

[tpacif20]

Re: Concrete slab question

I need to find a site with step by step instructions,with pictures on how to pour and c build the forms for the slab, Wood size,how much graval,rebar placement etc...