vermicrete

[h12rpo]

Still flapping about this........someone mentioned mixing the water and opc first then adding the vermiculite to the mix in a dustbin........what proportions water to opc ? Or if easier what consistency ?
And is as handful of lime recommended to be added.?

[faz]

You want the OPC/water mix to be a runny slurry so that you can get it to coat all the vermiculite, not sure exactly what sort of proportion I used though. I added about a litre of lime to each 100 litres of vermiculite. I am not sure what effect that had but I had very few problems with the vermicrete if I am honest - not sure why as most people seem to hate it!

[h12rpo]

Ok thanks faz .....should be on it in the next week or so

[johnaero]

this for base of outer walls? i took the advice on here and went for breeze blocks for base.

outer walls i said just wrap it in 3in ceramic blanket, think 3inch blanket same as 6inch vermacrete.

then just skim it with stucco

[cannyfradock]

....I started to add lime to the vermecrete as it makes this "devil's porridge (can't remember who called it that) more sticky and easier to manage. If you use lime, don't forget to don the marigolds.

I haven't tried the dustbin method, though it sounds a good idea. I've used the empty 1 ton ballast bag...and a cement mixer. I found the cement mixer worked best but you need to add a touch more water for the stuff to mix well in the drum.

I'm not sure on the thermal value's of blanket compared to vermecrete, but if I was going to finish the dome with a waterprooff render (stucco) I would put the render on vermecrete.

Terry

[pete123]

Hi,

I mixed it up dry & then plonked it all on by hand (with marigolds to prevent lime)

ukwoodfiredovenforum.proboards.com/index.cgi?board=pompeiiovens&action=display&thread=296&page=17

I can't remember why I didn't use lime?
If you click on the above link and go back a page there is a link to the vermiculite maker's website with advice on it.

Pete

[johnaero]

was gtting the specs from the forno pdf file. think lot have got good results from using chicken wire over insulation for stucco to bond

but i am only going buy what seen read. hopefully in few weeks i can tell you if worked of failed awfully. 1 huge plus i found was 3inch insul was half price vermacrete mix.

[jock]

Is it possible to coat the vermicrete directly onto the firebrick or clay brick dome?

[faz]

Yes you can put the vermicrete directly on top of your dome bricks. Many people use a thermal blanket first for extra insulation, but if you miss this out make sure you use 4 inches absolute minimum thickness of vermicrete.

[jemb]

i did exactly that but 150mm thick

[bookemdanno]

That'll be just fine Jemb!