Vermiculite only insulation?

[gerryready]

Re: Vermiculite only insulation?

new to site and interesting, I was thinking of making a frame box, or biscuite tin, about 12in by 12in, by 2in depth. Then line inside the frame with ally foil leaving excess to fold over later. Fill the foil with vermiculite, then fold over with the excess ally foil , and you have made a vermiculite brick.Make sveveral bricks until dome is covered. Then cover with chicken wire, then cover with 2in vermiculite concrete mix and let set. If I am correct that would be a better way than a solid vermiculite concrete mix, with more expansion. I am making one on a trailer, so i have loads of questions, if anybody can help

[jzman123]

Re: Vermiculite only insulation?

Hi All,

Well, it has been a couple of years since I finished and everything is holding together quite well.

As for the vermicrete cladding on the dome, I ended up just using straight vermicrete (probably a little more vermiculite than normal to keep it light) and trowled about 4-inches on the dome and the transition to the chimney.

Then I backfilled the entire brick enclosure with loose vermiculite and it insulates very very well and retains heat for about 3-days. We'll fire it to about 950-1000 and then on the 3rd day, it'll be about 300 in the dome and 250 on the floor. Plus, I don't have a very good insulating door. I just used a double-thick layer of 5/8" drywall and covered it with aluminum foil as a temporary solution. After 2 years, I am still using it and it works great.

Best,

JZman

[david s]

Re: Vermiculite only insulation?

new to site and interesting, I was thinking of making a frame box, or biscuite tin, about 12in by 12in, by 2in depth. Then line inside the frame with ally foil leaving excess to fold over later. Fill the foil with vermiculite, then fold over with the excess ally foil , and you have made a vermiculite brick.Make sveveral bricks until dome is covered. Then cover with chicken wire, then cover with 2in vermiculite concrete mix and let set. If I am correct that would be a better way than a solid vermiculite concrete mix, with more expansion. I am making one on a trailer, so i have loads of questions, if anybody can help

I think this is a pretty good idea. It gets around the problem of having to remove lots of water. It may also be prudent to poke quite a few small holes through the foil bricks to allow moisture out.

[david s]

Before the advent of Ceramic Fibre Blanket that is exonerated as a Class 2 carcinogen, I used to do two 35mm layers of vermicrete with a week of drying between layers ( a thicker layer does not allow moisture deeper in to dry fast enough).
Now, because the newer generation of exonerated blanket has come down closer to the older non-exonerated stuff I use blanket topped off with a layer of 10:1 vermicrete which has around the same insulation value as blanket for the equivalent thickness.I find 10:1 is about as lean as is comfortable to go without it being too crumbly.
A mix of perlite and vermiculite also seems to work better than either of them alone. A handful of powdered clay for every litre of GP cement imparts more stickiness to help application.

For this interested here's my 10:1 recipe:
By volume;
5 parts medium grade perlite
5 parts fine grade vermiculite
1 part GP cement (+ a little powdered clay)
4 parts water

Mix dry ingredients then add water slowly folding in as you go (best done in a barrow)
If water pools in the bottom add a little more dry material. Too much water will wash the cement off the grains of perlite and vermiculite.

[UtahBeehiver]

Daidensacha, I think it is time you start your own construction thread rather than us an old thread, this way all your questions and post will be in you own thread. Also, once the thread is made, I will move post from this thread over to yours.