Foundation Question???

[kibarn]

Anyone have advice on how I should make the poured foundation for the Pompeii oven (thickness, etc.). I live in Massachusetts and i'm worried about frost heave destroying my foundation and eventually my oven. I also am on a tight budget so i do not want to overbuild too much.

[RTflorida]

Check with your local building dept. When it comes to foundations it is highly advisible to follow "code" for your area. Frost heave and soil composition are both taken into consideration. Remember this, the foundation will be supporting thousands of lbs., the slightest movement of a foundation can cause a disaster or at the very least cracking that is both unsightly and a pain to repair.
I'm guessing that for your area the frost line is in the 36" - 48" depth range, meaning you will need footers down to at least this depth.

RT

[Versachi]

I think I have touched on this before but here it is again. There is no need imo to put you footing below the frost line if you take care to prep the soil. I dug down 16 inches or so and 16 inches out from my slab and put good granual A gravel where my slab would be located. I have no worries.

Here is an article from Walters Forensic Engineering Inc. that may ease you mind. http://www.waltersforensic.com/artic.../vol1-no11.htm

Cheers, Versachi

[Acoma]

Great find Versachi. RT, I went below frost level (2ft. footers). KI, what Versachi provided was of 3 choices, you must do one of the three without shortcutting. If you shortcut, you pay the price in the end. Every step towards the completion of the oven must not be shortcutted, the rewards being unbelievable, enriching to you and to those you share with.

[RTflorida]

As I mentioned soil considerations are the primary variable in dealing with frost heave. Again, simply consulting with either the local building dept or a masonry contractor in your area should both tell you what is needed. You may get lucky and only havr to go 16" deep. But get the experts opinion.

[Inishta]

Originally Posted by RTflorida

I'm guessing that for your area the frost line is in the 36" - 48" depth range, meaning you will need footers down to at least this depth.

RT

RT.................does this mean that you need to pour a slab this deep, at this depth or do you pour footings for the footprint of the walls as in house construction? This is not relevant to my build but I'm sure some others are a tad confused. Seems like a whole lot of concrete.

[RTflorida]

Inishta,
a footing is usually 8", 10" or 12" wide and is the below grade foundation of the structural walls. You can then either tie in you slab (at ground level) to the footings and begin you block stand on top of this OR set your stand bricks in the footing (the block can also be used for the footing)

And yes, after taking in all of the variables (depth at which the ground freezes, soil density (sandy, clay, rock), and drainage are the key factors used to determine a foundation depth. 36" is not unusual, 48" where it gets really cold. In my early years I lived in NE Ohio, The frost line there was 36" at the time. No I don't think it ever actually froze to that depth, but due to the poor drainage of the entire area, code was still always 36", with the thinking being excessive water around the foundation could cause a heave situation even before the ground could freeze solid - as my father would say.

Really, we all ask each other for oven guidance on this forum. Don't be shy in asking contractors or inspectors the right way to do it for you area. Its just a few phone calls, your not buying from anyone and certainly not obligated for anything. I would rather have the added piece of mind knowing I did it right, than left wondering - well, I saved $100 on cement, sure hope the foundation is deep enough to not move.
Just my 2 cents (its all I have left after Christmas shopping)

RT

[Inishta]

Thanks for that RT. I had visions of 4 feet of concrete..................

[thebadger]

Kibarn,

I live in SW Ohio and struggled with the same question. A big thanks to Uno and others for helping me out. You may want to do a search on Foundations on the Forum as well.

What I decided was to dig down past 30 inches (frost depth here) and put in a 6+ inch thick footer. I then dry stacked my blocks (~4 course below ground/~4 courses above ground) and then I poured concrete/rebar in EVERY core for good measure. I did this all by hand and with "bagged" concrete. YES I should/could have gotten a concrete truck but this allowed me a lot more control given weather, work and helpers. It actually wasn't too bad ~2 FULL days of digging, 1 day for footer, 1 day to dry stack and 1 day to fill the cores. (Did I mention the drain pipe I had to re re-route

Not sure where but I think someone posted a reply about a new footer technigue. Basically you don't have to dig down as deep but you have to insulate under and to the sides... Basically preventing the soil underneath from freezing. Might be worth checking into.

Good luck and happy holidays.

Dick

PS I think it's definitley something to think about as other pointed out, if you have a bad foundation you could put your whole project in jeopardy.