foundation size

[astroflash]

Hi,
I'm getting ready to build a 42" oven and have started on the foundation. I need some help in the actual foundation size. In the oven plan, for a 42' oven, a chart gives a size of 77' X 86". However, in the materials list at the back of the plans, the foundation size for a 42' oven is 80"X 94". Can someone help clear up my confusion?
Thanks,
Barry

[Breven]

Re: foundation size

Not sure Barry. Go with the bigger one. Having a little extra space is better than not having enough!

[Jed]

Re: foundation size

The best way to confirm what you need for your oven is to do the math...

Start with the width of your oven, 42 inches;.. Add the brick in the oven wall (if you will use a 9 inch fire brick, cut in two, 4.5 inches, on each wall, two walls) 9 inches; add the amount of insulation you will use on the outside of the dome (perel? or vemicrete? or batts? of insulation) 3 or 4 inches on each side?; and then add the size of the exterior cover or wall for your oven. Will you use a stucco - igloo? or build a frame structure with 3.5 inch metal stud walls? - one on each side

Add up all the pieces and that is the minimum width you want on your base walls, and then add a couple inches on each side for your foundation.

You will probably choose to make the foundation deeper than it is wide. The reason is to add a bit of counter space at the front of the oven so you have a place to stage food on the way into and out of the oven.

My suggestion is to do the math! and you are sure to end up with a foundation that will fit your oven..

Good luck with your build and be sure to send in pictures for us to see!

Thanks,

JED

[Dino_Pizza]

Re: foundation size

Barry, just to add to what Breven and Jed said, 16" concrete blocks that you buy at any Home Depot, lowes etc. are 15 5/8" long. So for a 42" oven, if you look thru the Forno Bravo photo gallery seem to almost always be 4 1/2" blocks wide by 5 blocks deep or: 70"x78". This works out good for the enclosed (dog-house style) but you could also go 4 1/2 blocks deep if you cantelever the counter out the front. I did not do an igloo style but I believe the dimensions are similar although many have done corner installations or used a round or "diamond" shaped base (with the corner cut straight for the counter or shelf) recently that look really nice and seem to take up less room in the yard.

Also, the 70x78 info above is with using FB insulation blanket at 2-3" deep. If you rather use the vermiculite-concrete mix insulation, that has to be 4" deep so that dimension I mentioned might be another 1/2 block or full block wider and deeper. Man, I hope I helped more than confused -Dino