Horticulture Vermiculite

Posted by Rado (144.134.149.197) on October 31, 2004 at 15:43:08:

In Reply to: Horticulture Vermiculite posted by August V on October 29, 2004 at 00:39:33:

Vermiculite from landscaping suppliers is the same as they also use the exfoliated expanded form as is used for insulation. It's light in weight and soft, flat, you can squash it in between finger nails. 5mm plus granule size is fine (not really the mineral dust.)

6:1 ratio for mixing is good and reinforced with mesh inside - here we are talking about insul. under the herth slab. If you had for instance corrugated iron under, etc., you can use even less cement making it less heavy therefore less heat absorbing. Portland cement for mixing/bonding is fine. 2 inches + layer is ok, more you apply the better. Heat eventually soaks through this insulation layer although you can not feel it as hot as if the insulation wasn't there!