Ideal dimensions for a pizza/bread oven

[KarenT]

I have a fairly confined space where I would like to build a wood fired oven outside. The dimensions for the pad are 105cm wide x 97cm deep. I want to maximise the inside dimensions as I make a reasonable amount of sourdough bread and pizza. Any suggestions of the design would be greatly appreciated eg, suggestions on flue position/ openings etc for optimum cooking.
Cheers
Karen

[SableSprings]

Welcome to the forum Karen. I bake mostly bread (baguettes & sourdough boules) and some pizza in a short beavertail/dome oven (basically a Pompeii) that's a meter (39") in diameter at the widest. The one thing you need to decide is if you want a half-barrel or dome style. Either design works well, but if I was baking mostly bread in quantity I'd lean toward the barrel type simply because you can load and work pretty large batches more easily. Although I love my oven for pizza, I am limited to 10 baguettes at a time.

My advice would be to use a cardboard cutout to see what will work best for your baking plans. Don't forget that you are going to want 6-12" inches of insulation all around the upper section (thickness will vary depending on whether you are using perlite/vermiculite or ceramic batting) . The mantra here is to put as much insulation on as you can afford (space & money). Don't forget that you will need to add 2-4 inches of ceramic board between the top slab and the oven build. You might want to use some lateral extra space to plan a work/prep surface (offset the oven). Also plan for where to put bread batches for cooling after they are baked and wood storage/access. Lots of options here, so spend some time looking at the builds (some great ones brought together by LBurou) in the top newbie link

http://www.fornobravo.com/community/...n-the-archives

Good luck and looking forward to your build.

[JRPizza]

Hi Karen, you give a width and depth to your slab - is the oven orientation optional, or does the opening of the oven need to face the short side? Ovens tend to be longer than they are wide, and with a small slab you could gain some size by placing the oven along the long axis. Another thing to consider is do you have room for your hearth to overhang the pad? Your 105X97 pad is going to force you into a smallish size oven with possible compromises in oven wall thickness and/or insulation. Making the hearth overhang the pad would give you more room for a larger oven. Using the materials I used for an example (pardon the inch units) my oven walls were half brick deep (4.5"), planning on 3" of insulation, and at least 2" of render/cover over the insulation. Doubling those dimensions as they are on both sides of the oven you have 19" ~(48cm) which would leave just over 48cm (19") for your oven inside diameter which seems very small. You could go with a thinner shell (less mass for heat) or less insulation (oven would lose heat more rapidly), but extending the hearth would probably be a better option.

[RandyJ]

Sable I think you you were thinking inches not cm. You would need 5 to 10 cm under the oven and 5 to 8 cm around the oven and over the top. But as he said use as much as you can afford. You will have better performance.

Randy

[KarenT]

Thanks for the replys. Unfortunately JR, it needs to oriented on the lesser width as I don't have the space. Using inches now for you guys- so if its 38" in diameter, I need to allow for bricks, 3" of insulation and 2" of render. I'm wondering if it is going to be worth it for a 19" oven. Sable, is your oven similar in size? ideally i'd want to cook 2 pizza's or loaves of bread at a time.
Cheers
Karen

[david s]

If you go for a modular cast oven the walls are usually much thinner (approx. 2"). That would give you more space.Also the render does not have to be so thick, I use only around 3/4" thick. The outer shell is only for weatherproofing, you don't need to park a tank on it do you?

[JRPizza]

David, using a cast oven, minimal render, and whatever you recommend for insulation, how big of an oven do you think Karen could get on a hearth that size?

[david s]

David, using a cast oven, minimal render, and whatever you recommend for insulation, how big of an oven do you think Karen could get on a hearth that size?

In my case the supporting slab is 36" x 36" (910x910 mm) and oven interior is 21" (540 mm) diam.

[SableSprings]

Sable I think you you were thinking inches not cm. You would need 5 to 10 cm under the oven and 5 to 8 cm around the oven and over the top. But as he said use as much as you can afford. You will have better performance.

Randy

Thanks for catching my conversion/unit error Randy...I could blame it on my martini but I'd never forgive myself if I blamed anything on Hendricks. I've gone back and corrected the error...please forgive me Karen

Thanks for the replys. ... Sable, is your oven similar in size? ideally i'd want to cook 2 pizza's or loaves of bread at a time.

My inside oven dimensions are 45" deep and 39" at the widest point of the internal curve. David S (post 8 above) cooks a lot with his 21" (54 cm) oven and if I remember correctly he's put lots of pizza and plenty of bread loaves through it. Based on several years of using my oven, I think I'd want one of any size and 21" ID is plenty for lots of good eats. I don't see that you'd have a problem putting out several loaves of bread at a time from a 21" hearth. Since there won't be a fire in the oven when baking bread-how many loaves you can bake at a time will obviously be based on loaf size(s) and how you can fit them onto the hearth. As for pizza, remember the size of the pie is variable...you simply need to adjust the skin size so you can cook your pie with a fire going to keep up temps (I like smaller ones simply cause everybody gets to try lots of flavor combos without getting full).

As I mentioned earlier, making a cardboard cutout/template of the proposed hearth size would let you see and measure the layout and working space you'll have. It's also handy to use when estimating the brick/insulation/render around the hearth. The ceramic insulation will allow you the most bang for your buck and minimize the space that's used for the insulation layers. Also make sure that you will have space to fit a 1/2 sheet pan through the opening and on the hearth

p.s. The hearth cutout is also useful to plan potential loading arrangement and size of loaves...