Insulation for pizza oven that withstands heat

[Danii KD]

Hi,

I will have calcium silicate board under the pizza oven but I have a question regarding the insulation around the dome. The insulation I found at the usual hardware stores is Isover and it says max temp 400 degrees. At the same time, it says non-combustible. The dome will probably get much hotter. Will this still work? I'm considering 5 cm thickness, is that enough?

 

[Dan_Johansson]

Ceramic fiber (which is no longer ceramic) is what you need. 5 cm is enough if it's just pizza you have in mind...

Stone wool can withstand very high heat (within reasonable limits) without starting to burn, but the binder in the insulation breaks down over about 200 degrees.. This causes the insulation to compress and lose its insulating ability...

 

[Matti_75]

Vermiculite

 

[Dan_Johansson]

Vermiculite

Vermiculite does have decent insulation properties when it's "loose," which creates some problems when trying to insulate a wood oven with it... You kind of have to build the outer shell first and then fill the space in between with vermiculite... The advantage of ceramic fiber is that you can plaster directly on it...

I myself have 50-100 mm ceramic fiber and then the "rest" filled with regular rock wool, but I've built a "house" over my oven...

 

[Danii KD]

I don't just want it for pizza but to be able to use it as an oven for almost everything. I can't seem to find any ceramic fiber for private individuals. Maybe it's easier to cast vermiculite with refractory mortar a few centimeters and then add thick Isover insulation?

 

[Dan_Johansson]

https://www.amazon.se/YJBE-fiberfil...cphy=1012581&hvtargid=pla-1279095558132&psc=1

First result for "ceramic blanket"..

Otherwise, "superwool" is a common trade name...

 

[Dan_Johansson]

http://www.cebex.se/advanced_search_result.php?keywords=Superwool
Seems to sell to individuals...

I've personally shopped at Bevego in Trollhättan..
https://bevego.se/kategorier/teknisk-isolering/hogtemperatur/607-ht#

 

[Dan_Johansson]

I don't want it just for pizza but to be able to use it as an oven for almost anything. I can’t find any ceramic blanket for private individuals. Maybe it’s easier to cast vermiculite with refractory mortar a few centimeters and then add thick Isover insulation?

A few centimeters aren't enough to get the temperature below 200 degrees... If you're going to do anything other than pizza, it's worth (read necessary) to spend money on the insulation, plus you should think about how you can close the opening, otherwise, the heat will escape quite quickly...

 

[Danii KD]

[link]

First hit on "ceramic blanket"..

Otherwise "superwool" is a common trade name...

Tried to order there but quickly got a response that it was out of stock. Will check your other links

 

[loffman]

Tried to order there but quickly got a response that it was out of stock. Will check your other links

Take a look here. Bought some stuff here for my oven.
https://www.kamintillbehor.se/byggmaterial-till-pizzaugn/

 

[Danii KD]

Take a look here. Bought some things for my oven here.
[link]

Yes, I found it later, looks really good! Will order from there. What diameter for the smoke pipe? Is 8 cm good?

 

[loffman]

8 cm is way too small. I went with 15 cm. If I did it again, I probably would go for 20 cm, but 15 works...

 

[Danii KD]

8 cm is way too small. I went with 15 cm. If I were to do it again, I would probably go for 20 cm, but 15 works...

Okay, I thought one wouldn't want to lose too much heat. What would you say is the effect of 20 cm compared to 15? Does it burn better?

 

[Dan_Johansson]

I also have 15 cm, and would have gone for larger if I did it again.... Now I only have a meter of chimney, it might possibly draw better with a longer one...

 

[Dan_Johansson]

Okay, I thought one wouldn't want to lose too much heat. What would you say is the effect of 20 cm compared to 15? Does it burn better?

What happens is that the smoke goes the wrong way, out through the opening... If you want to retain maximum heat, you need to build a completely different type of oven...