Vermiculite Micafil is an excellent loose-fill thermal insulating material. Vermiculite reduces the loss of heat in cold weather and keeps the interior cool in warmer weather. Vermiculite is a naturally occurring mineral - easy to handle, sound absorbent, resistant to decay, fire-resistant, odourless, fibre-free and non-irritant. Vermiculite is relatively simple to install. Poured from the bag, it allows flow into and over all potential heat loss areas. Vermiculite can insulate loft floors with a continuous heat trapping carpet of insulation. This can the be brushed or leveled by hand to finish