Does Vermiculite Insulation Absorb Water

Vermiculite is an aluminum-iron-magnesium silicate that resembles mica in appearance. For use in horticultural applications, vermiculite is heated to expand the particles. This expansion enables it to absorb moisture when used as a potting medium. Vermiculite can soak up 3 to 4 times its volume in water.

What happens if vermiculite gets wet?

Vermiculite insluation itself does not burn: it is non-combustible, though contaminants and debris, if mixed with any insulating material at enough volume, might burn. When wet, vermiculite can hold a lot of water, as much as 220-325% by weight, and as much as 20-50% by volume.

Does vermiculite help with drainage?

Both perlite and vermiculite are put to use in the garden to improve drainage, prevent compacted soil and increase moisture retention. … The amount of water that vermiculite holds is too much for plants like cacti, succulents, or rhododendrons, which need a well-draining soil.