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gummz 09-25-2010 09:34 PM

Help please: Insulation Depth Problem
Hi Everyone.

I've run into some problems while build a vault oven (yes yes i know ....). I'm hoping someone might be able to help me find a solution(s) to my problem(s).

Basically where my side walls are, i rushed my concreting and the walls "bowed" and push out. This now leave me with very limited space for insultion, maybe ~5cm (with a brick exterioir) or maybe about 10cm if i get rid of an upper brick exterior and do some sort of metal housing cage.

Given say 5~7.5cm of space, what would you use to best insulate the oven?

Would really appreciate any advice and/or help.



lwood 09-26-2010 05:36 AM

Re: Help please: Insulation Depth Problem
Pictures would help a lot.

dmun 09-26-2010 01:13 PM

Re: Help please: Insulation Depth Problem
50mm = 2". That should be enough for refractory blanket on the sides. You will want a little more on the top, where presumably you have more room. Heat rises, after all.

That wouldn't be enough room for vermiculite concrete insulation, where you need at least four inches.

Tscarborough 09-26-2010 02:21 PM

Re: Help please: Insulation Depth Problem
Blanket is your only good option.

gummz 09-26-2010 03:28 PM

Re: Help please: Insulation Depth Problem
Morning All,

Many thanks for your responses.

Would 2 inches be enough or is it just the best possible solution for my issue. Do you think a few insulating firebricks would help?? or not worth the money?

I had originally thought of having a brick enclosure but now thinking or maybe opting for the metal struss designs i see many of the people on this forum are build (Dinos fantasic build for example). I'm hoping to "free up some space" so i can try and best mimic (as best as i can) the 1" Blanket and 3" vermiculite method of insulation.

Yeap i will try post some pics. Thanks for helping out, i've lost a lot of sleep and been worried :)

alexi82 10-08-2010 12:01 AM

Re: Help please: Insulation Depth Problem
hey mate,

what did you end up doing?

I had a similar problem only it wasn't because i rushed the concrete, it was cause I rushed the form. anyway, i have about 2-3 inches of cladding, and on one side i have about 4-5 inches of space for insulation, on the other i have about half an inch...DOH. but i am hoping the cladding is thick enough, and the concrete blocks on the outer wall will be enough.

i was thinking of pouring some vermiculite into the cavities of the concrete block on the side that isn't insulated...and also adding some more 12:1 vermiculite:cement mix on top...

gummz 10-12-2010 11:18 PM

Re: Help please: Insulation Depth Problem
Hi Alexi82,

I saw some pics of your build, looking good~!

I'm still at the same point, i just have too much work on atm to work on the oven, but next week or the week after i'm gonna take a day off to work on the vault (roof of chamber).

Have you thought of anything??? i was thinking insulting firebricks cut in 1/2 ....

alexi82 10-14-2010 04:37 PM

Re: Help please: Insulation Depth Problem
hey gummz...

on the side that was too narrow, i just ensured that there was concrete cladding all the way up to the outer besser block walls...and then filled the cores of the besser blocks with vemiculite. its something at least.

the other sides i just ensured there was a few inches of cladding, and then on top of all of that a 12:1 vermiculite-cement mix of about 2 -3 inches all over.

it's probably not perfect, but its going to do the job i think.

couple more curing fires before i fire this puppy up.

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