Vermiculite or Perlite

[ShannonCorum]

I'm sure this has already been answered somewhere, but I can't find it so I thought I'd just ask.

I have a choice of medium grade vermiculite or coarse grade perlite at my local Home Depot. Which would be better?

I plan on using it to insulate under my over floor and also to insulate over the dome (both as a mix with concrete and loose over the dome).

Thanks,

Shannon

[david s]

Re: Vermiculite or Perlite

Perlite on its own is a better insulator, but once mixed with cement there is little difference. I dislike the the fine dust that perlite contains. It is an irritant if you inhale it (wear a mask) never have a problem with vermiculite re this. I can't explain why but if you are mixing with cement a 50/50 mix of perlite and vermiculite makes up a much more workable mix than either of the two alone, particularly if you are making a lean brew.

[ShannonCorum]

Re: Vermiculite or Perlite

Thanks. The Perlite is about $4 less per bag than the Vermiculite for the same size (2cu ft). Didn't know if the coarse texture perlite was better than the medium of the vermiculte, or vice versa. I don't think Home Depot carries it in store for very long each year so I want to go ahead and grab it while I can.

Shannon

[david s]

Re: Vermiculite or Perlite

You may be able to get it cheaper in larger bags (4 cu ft) from nurseries or hydroponics suppliers.