insulation question

[ikhan42]

Hi Everyone,

Am about to lay footings and actually get this oven started after all these years, I am looking forward to the construction.

I have a question with regards to the dimensioning the instructions talk about 1x3 inch Fornobravo insulation blanket. What I was thinking of doing was actually having 2x3 inch insulation blankets and then also adding approximately 2 inches of vermiculite between the blankets and the housing enclosure.

Anyone got any thoughts on if this is a good idea/ bad idea?



Regards
ikhan42

[Aegis]

From all that I read on this forum, you cannot have too much fun and you can not have too much insulation! But I would do the blankets and then pour vermiculite on top of, and all around the oven.
Good luck on your journey and enjoy your build!
John

[ikhan42]

Originally Posted by Aegis

From all that I read on this forum, you cannot have too much fun and you can not have too much insulation! But I would do the blankets and then pour vermiculite on top of, and all around the oven.
Good luck on your journey and enjoy your build!
John

Aegis,

Thanks for the info I will have about 2 inches between the 2 layers of insulation blanket and the outside wall side to side and have more space front to back I will also have about a foot between the top of the oven and the roof I will be building so I am going to basically do the blankets and then fill the rest of the housing with vermiculite, my only concern is that to do with the weight on the dome.

Is vermiculite light or heavy the pictures I have seen give me a indication that its light but have never seen or held it in real life.

Regards
ikhan42

[Tscarborough]

It is very light.

[david s]

If you can't access vermiculite you can alternatively use perlite, which is a slightly better insulator.

[ikhan42]

David,

Perlite it will be then I want to use products that will give maximum effect insulation wise so if Perlite is better then vermiculite then perilite it is.

Thanks
ikhan42

Originally Posted by david s

If you can't access vermiculite you can alternatively use perlite, which is a slightly better insulator.

[chidding]

As for the weight, its basically superlight foam.. 100litres was around 2kg or so .. from memory..

[azpizzanut]

Hi Ikhan,

See my build #2. I used aluminum window screen around my oven with 4"-6" spacing. No need to put expensive insulation in the corners where it doesn't do any good.

Any of the dry-fill insulation will settle over time, in an enclosure, so build up the top layer or place something to restrain it from flowing down hill. Also, use fg house insulation to block off between studs or any place you don't want loose insulation to migrate. Perlite and vermiculite will find its way through a small void and drain out if you are not careful.

I put perlcrete and rockwool around oven #1 then poured perlite over the top of that. Oven #2 has FB ceramic blanket insulation and loose vermiculite.

Cheers,