Where can I find vermiculite in the US?? The only thing I find is garden stuff.

[Bethencourt]

Hi,

I've been trying to find Vermiculite but I can only find the garden one, not construction.
I'm almost ready to start the building. Planning to pick up the calcium silicate boards, Ceramic blanket, etc this Friday.

Does anyone have any recommendations?

thanks!!

[Bethencourt]

I found Pool Krete Pre-Mixed Vermiculite on Facebook Marketplace for $15 per 40Lb bag.
Would this work??

[Neil.B]

I'm not in the US and don't know if there is a difference, but try looking for chimney insulation as vermiculite is used between chimney liner and bricks.

[UtahBeehiver]

Look at perlite then. I should be available at any masonry supply store. It is used to insulate Concrete Masonry Units (CMUs) by pouring in the cores. 5 to 1 ratio for floor insulation, 8-10 ratio for dome and interchangeable with vermiculite.

[CapePizza]

Hello Bethencourt. I've been keeping a file I call "oven notes" which includes info I've found that may be helpful for me in my build. I saw your post and had the following in my notes. for what it's worth, and I would do your own research, but this is info I had gathered regarding vermiculite vs perlite:

Caution. Perlite can be coated with silicone to make it slide easily into block cores, where it's commonly used as an insulator. Make sure you locate plain, horticultural grade perlite, not the construction grade. The insulative properties are nearly identical. Use perilite as opposed to using vermiculite. Vermi is softer whereas perl is harder. Go with perlite and hard strength cement.

I'd like to hear what others may have to say as the info may..... or not .... be helpful.

[UtahBeehiver]

I used commercial grade perlite for my dome pcrete and did not have any issues with the coated perlite. More important is using the correct consistency, not too dry, not too wet, not too thick at all at once.

[Chach]

Masonry Perlite is coated with silicon to make it more water repellent and has nothing to do with it to easily slide in the cores of cmu block. It won't wet with cement but It should work fine as Russell's experience suggested. The cement holds the perlite in place not the other way around so coated or not the cement will bind it together and will function as intended. This also isn't your finish coat and your render will lock this layer in futher.

Also, poolkrete will not work for you as it has way more cement in it and will not be a good insulator. Its just a softer cement product used for for the floor of inground pools that utilize a vinyl liner. Not what you are looking for.

Ricky

[CapePizza]

ah... thanks for clarifying, Ricky, regarding the silicone coating and the water repellency. Maybe that is why it's more difficult to mix with concrete than vermiculite?

[Bethencourt]

Hello Bethencourt. I've been keeping a file I call "oven notes" which includes info I've found that may be helpful for me in my build. I saw your post and had the following in my notes. for what it's worth, and I would do your own research, but this is info I had gathered regarding vermiculite vs perlite:

Caution. Perlite can be coated with silicone to make it slide easily into block cores, where it's commonly used as an insulator. Make sure you locate plain, horticultural grade perlite, not the construction grade. The insulative properties are nearly identical. Use perilite as opposed to using vermiculite. Vermi is softer whereas perl is harder. Go with perlite and hard strength cement.

I'd like to hear what others may have to say as the info may..... or not .... be helpful.

Thanks everyone for your answers!!

CapePizza Where can I find your file?

[CapePizza]

It's just a personal file I've been adding to when I see something that might pertain to my build, like keeping notes. I didn't post it anywhere.

[Chach]

ah... thanks for clarifying, Ricky, regarding the silicone coating and the water repellency. Maybe that is why it's more difficult to mix with concrete than vermiculite?

there is also non coated perlite. It is used in lightweight concrete but the cement content in that is much higher than you would be using.

Ricky