vermiculit

[Greenman]

Re: vermiculit

The vermicrete is not particularly 'sticky' and the chicken wire over the Ceramic Fibre certainly helps hold it in place until it goes off properly. The stucco keys into the vermicrete very well due to the surface and IMHO there is no real need for reinforcement there. If you feel the need for reinforcement then fibres in the render will do the job fine.

It will be interesting to see your pics when you put them up.

Cheers ......... Steve

[david s]

Re: vermiculit

I don't like to add anymore water to the vermicrete layer especially after removing it all, but I prefer to wrap the whole oven in cling wrap after the stucco layer and let it cure for a week.if you do more than one layer of stucco then just wrap it after the last layer.This technoque does a pretty good job, you can see the moisture trapped under the cling wrap.

[campbelloakland]

Re: vermiculit

It has been a while but we set the Premio2G100 oven in place which was no easy feat. When my sons showed up they were wondering what I was doing with a gantry in my truck. They soon found out, it was the only way to get the pieces on top with the limited space we had. Anyway, it is all cemented together and has dried out during the week. The thermal blanket and chicken wire go on tomorrow and then the vermicrete.

Hopefully my last question. Not being a mason and all I have read and see two different approaches for applying the rendering/stucco over the vermicrete. In one case they put another layer of chicken wire the rest they only say they apply the stucco to the vermicrete. When I see masons apply stucco to block walls they moisten the blocks before application which in this case defeats the curing of the vermicrete. Any recommendations....I just want to do it right. Some day I will get the pictures downloaded and show you our project. We are having a blast with this!!

[david s]

Re: vermiculit

Does anyone have an idea how many cubic feet of vermiculite I should have available to cover a Premio2G100 with a 2" layer of vermicrete? I was thinking of using 8:1 but I noticed in the stream 10:1 was used as well.

The more cement you use the less it will insulate. Some builders go as much as 13:1, but I find it doesn't stick together so well. I find 10:1 workable. if you are doing an enclosure it is better to fill between the oven and the enclosure with loose dry vermiculite or perlite, because both cement and water reduce insulation value and the water needs to be removed. If you plan on an igloo finish then you have to add the water and cement, because the mix needs to stand up on its own and be firm enough to render over.a 2' layer of vermicrete is insufficient insulation on its own over the dome IMO. You need ceramic fibre blanket between the dome and the vermicrete layer.

[campbelloakland]

Re: vermiculit

Thanks for the quick response! I am picking the oven up Monday and want to have all the ducks lined up. I have no experience with vermicrete but lots of experience of calculating bags of concrete needed wrong. Long story but I finally can do that right! Been waiting "patiently" since November to finalize this project. Cannot wait to start cooking. Thanks again!

[Gulf]

Re: vermiculit

2 times pi times radius squared plus 15-20%

What Russell said, but divided by 1728 (cubic inches in a cubic foot) .

[UtahBeehiver]

Re: vermiculit

2 times pi times radius squared plus 15-20%

[campbelloakland]

Re: vermiculit

Does anyone have an idea how many cubic feet of vermiculite I should have available to cover a Premio2G100 with a 2" layer of vermicrete? I was thinking of using 8:1 but I noticed in the stream 10:1 was used as well.

[bing]

Re: vermiculit

thanks. i will do it next week.

[david s]

Re: vermiculit

Yes, I do. The mix I use is 4:1:1 sand, cement, lime. I also add reinforcing fibres to give it more strength.

[bing]

Re: vermiculit

can i make stucco myself. is it mix of sand cement and lime?

[david s]

Re: vermiculit

Bing,
Two inches of blanket should be plenty. A lot of oven builders cover the blanket with a layer of vermiculite and cement because the creases and folds in the blanket leave an irregular surface. This vermicrete layer also adds additional insulation. One or two inches thick should be enough. If you decide to do this then a 10:1 vermiculite, cement ratio is better because it insulates better with less cement. Allow it to dry for at least week before doing the stucco over it.

[bing]

Re: vermiculit

is 5 cm (2") ceramic wool enough on the dome? i want to finish dome like igloo. find thing called stucco. can i make stucco with cement, lime and sand, and what ratio? no need to be waterproof becouse the roof over oven.

[sclancy]

Re: vermiculit

David

thank you for the quick reply!

I will have him omit the sand.

building a doghouse over it so no worries about the vermicrete.....

I found a source for bulk vermiculite quite cheap so no iso or blanket for me....gonna fill the house with 6-10" of vermiculite all around over a modular oven.

Looking to pour the vermicrete base 7" high for extra insulation and more height for my oven floor over the std 4 block high base.

[david s]

Re: vermiculit

The 5:1 vermiculite, cement ratio is correct for the under floor insulation slab. It is strong enough. Sand added will increase strength but reduce insulation value.

If you are building an igloo get your builder to mound your structural slab up slightly in the middle to prevent water penetrating under the vermicrete layer. If building a doghouse it doesn't really matter, you can keep it flat.