cooking floor design and dimensions

[ihughes]

Weather so bad here that I've looked ahead at what I'm going to do with the cooking floor. I've done a layout (see attached pic) and was looking for some comment.

I'm going with an igloo finish and a 36inch internal oven, probably with a high dome just to make sure my wife can fit her moroccan tagines in.

• I've centred the 36in internal oven on the hearth. Is that the best option or should I move it back half the width of the landing so the whole structure is centred on the hearth?

• Is one straight course out from the circular dome enough for the landing or should I add another full or half-brick course and push the floor back on the hearth to accommodate for the deeper landing?

• In either case, should the landing extend to the edge of the hearth or is that just a matter of how I want to finish off the oven?

• I was going to use fire brick for the landing, but would it matter if I used clay brick or some other kind of decorative brick as long as it will take the heat?

• I know I'll have to cut brick to shape the circumfrence, is there a better way than I've laid out to minimise cutting (he asks hopefully)? I want to keep the herringbone pattern because of its look

Cheers
ian

[DrDuktayp]

Re: cooking floor design and dimensions

You probably already have completed your herringbone pattern. If not I have one suggestion for getting the layout. You can snap chalk lines centered and at 90 degrees to one another. I laid this out in my tile program and you have lots of cutting regardless of where you set the pattern start. Luckily firebrick is easy to work with.

I saw a picture of an oven with a granite landing. You can get granite counter tiles that are 3/8 x 12 x 12 for about 12 bucks each. Don't know if it would hold up though.

DrDuktayp

[DrakeRemoray]

Re: cooking floor design and dimensions

Hi Ian, Have you already laid your hearth or are you still looking for feedback on this?

Drake

[dmun]

Re: cooking floor design and dimensions

You probably want more room in front, rather than in back. If your landing is too shallow, you won't have room to build your vent. I'd make the distance the same, sides and back, where it looks now like you have extra rear space.

Just as an aside, it looks like you have room for eight inches on insulation between the dome and the side wall. If you use a blanket, you can cut that down to six, and have a larger diameter oven. I went with a 36 oven because of space constraints, but it looks like you have extra room. Most builders would consider a 39 or 40 inch oven a lot more practical from a cooking standpoint than a 36. I've been hanging around here for a couple of years, and I never heard anyone say that they wish they had a smaller oven.

[ihughes]

Re: cooking floor design and dimensions

Thanks for the help.
The boss says she likes the igloo so leaving room for walls around the dome isn't an issue. I think I'll just have to insulate the dome a little more. There are 2 or 3 options in the pompeii plans, does anyone have a view on which is best for the Igloo?
1'' Insulfrax + 4'' vermiculite or
6'' Vermiculite or
2''-3'' Insulfrax

Drake, I haven't even laid the hearth yet as the weather has been too wet on my free weekends. Any pointers to reduce work greatly appreciated.

cheers
ian

[DrakeRemoray]

Re: cooking floor design and dimensions

I would just say (as Dmun says) make the dome as large as possible. I will ask someone else to comment on the best combo of insulation for an igloo finish.

I would aslo say that extra space at the front of the dome (landing and shelf space) is extremely useful. Having some shelf on the front of the stand is really helpfuly during oven use. I use the shelf in front of the oven to hold my beer, my ir thermometer, and sometimes a cutting board to unload a pizza onto...

Drake

[RTflorida]

Re: cooking floor design and dimensions

Since I did an igloo I will throw my 2 cents in concerning insulation.

As everyone keeps saying, you can never have too much insulation.
I used a 2" insulfrax blanket covered with 3-3 1/2" of perlcrete (perlite and portland cement)
This was then covered with 1" of type N mortar to give me a good uniform base for covering with mosaic tile. I used the fortified thinset for setting the tile.
According to my IR thermometer I have no more than a 5 degree increase in my outside dome temp - this is after having reached pizza temps and cooking several pizzas. On a sunny day.....I can't detect any rise in temp (the cobalt blue tile I used absorb a lot of the sun's heat)
As for heat retention, I have used my oven several times on the day following pizza making. If I put my non-insulated steel door in place right after the pizzas I will have an inside dome temp of 360-380 degrees and a hearth temp of 325-340 degrees the next day (24 hours later).

I've been totally happy with my oven's performance. Just remember, as the ads always say.....your mileage may vary.

RT

[jwnorris]

Re: cooking floor design and dimensions

<snip> ...and I never heard anyone say that they wish they had a smaller oven.

On the contrary, when I had finally decided to purchase my Casa series from FB, I could not decide whether to get the the 90 or the 100. Lucky for me they were out of stock pn both and I went with the Casa110. Glad I went bigger and never looked back.

J W

[dave d pizza lover]

Re: cooking floor design and dimensions

i am done thru the concrete hearth and was wondering if in stead of pouring a vermiculite slab i could put a couple of extra courses of firebrick at the base since i have a lot of culls left from a job thanks dave

[Dutchoven]

Re: cooking floor design and dimensions

Dave,
Extra firebrick would only be good if you wanted greater thermal mass. They would not be a substitute for the insualtion layer of vermiculite concrete. They would also eventually transfer the heat to the structural slab further wicking away the heat from your oven.
Hope this helps!
Dutch

[RTflorida]

Re: cooking floor design and dimensions

Dave, not the best idea. Adding more firebrick instead of the vermiculite will add more thermal mass - resulting in considerable heat loss out of the bottom. You would need longer, larger, hotter fires (considerably more wood) in order to maintain pizza baking temps. The vermiculite concrete layer is your insulation - for retaining the heat within the hearth bricks and dome.

The only other options I would consider would be perlite (another organic insulator like vermiculite) or the light weight insulating boards such as CalSil that FB sells - which has the best insulating qualities.

RT

[dave d pizza lover]

Re: cooking floor design and dimensions

thanks dutch this project is taking a life of its own really enjoy the forum its very informative

[Hendo]

Re: cooking floor design and dimensions

• I was going to use fire brick for the landing, but would it matter if I used clay brick or some other kind of decorative brick as long as it will take the heat?

• I know I'll have to cut brick to shape the circumfrence, is there a better way than I've laid out to minimise cutting (he asks hopefully)? I want to keep the herringbone pattern because of its look

Ian,

I too am contemplating using other than firebrick for my landing - I'm probably going to use the same 30mm granite as the adjacent bench-tops, supported by a small slab of concrete to bring it up to the same level as the firebricks. From reading other members' posts, many have gone to a different medium here without any dire consequences. I've seen some really cool photo's of oven mouths with a 'smoke layer' at start-up which clearly demonstrate the delineation of cold air entry in at the bottom of the vent landing and hot air/combustion product exit out at the top and up the chimney.

The only concern I have is radiant heat - but really, it's getting a long way away from the heat source so I trust this will not be a problem. Despite others' advice, I have incorporated an ash slot, so this should create an effective barrier between my firebricks and the granite landing, at least in terms of conduction of heat by neighbouring firebricks.

On cutting the bricks, I was dreading having to do this, but it was actually quite straight forward. The biggest issue for me was marking out the internal diameter accurately and making sure it was in the right place. Once the circle was marked on the bricks, it took all of about 45 minutes to rip through them with a wet saw. The picture shows what was achieved by someone who had never used such a saw before. I?m amazed at how circular it ends up looking ? after all it?s just a series of straight cuts. So if I can do it ?. !

Cheers, Paul.

[BrianShaw]

Re: cooking floor design and dimensions

Nice circle, Paul. I also like the ash drop. It looks quite spaciously sized. But... is that a gas pipe going into your slab, or are my eyes deceiving me?

[RTflorida]

Re: cooking floor design and dimensions

Maybe a lever for the ash drop???